What should you know before buying a home with a guest house or casita in Scottsdale?

Before you buy a home with a guest house or casita in Scottsdale, know that the City of Scottsdale treats a guest house and an accessory dwelling unit (ADU) as two different things. A guest house can't be rented on its own, while an ADU is a self-contained unit that can be, and which one the building is decides how it connects to utilities and what a lender will do with it. I'll pull the permit history and the zoning on the address before you write an offer, and I'll ask the listing agent in writing for the permits.

I'm Jen Keene, a REALTOR® with eXp Luxury in Scottsdale, AZ, helping people buy and sell homes, with more than 20 years in real estate and roughly 300 homes sold. The city and your lender decide the specifics on any one property, so what follows is what the Scottsdale Revised Code and the city's own pages say as of October 30, 2026, and the questions I would put to them.

The Scottsdale Zoning Ordinance defines a guest house as a detached, subordinate, accessory building used to accommodate guests of the occupants of the main single-family home, and it says a guest house is not a dwelling unit or an ADU. The ordinance adds four conditions. The combined gross floor area of the guest houses on a lot can't be more than one-half of the main home's, a guest house connects to the main home's electric, gas, water and sewer service and can't be separately metered, it can't be sold, rented or offered for rent independent of the main home, and it has to meet the setback rules in Sec. 7.200.A. The city's guest house page and fact sheet say the same things in plain language.

The ordinance also has the owner record a private deed restriction saying the guest house will never be sold, rented or offered for rent independent of the main home. The city's guest house page says this applies to any guest house built after January 1, 2025, and that the owner records the restriction before the permit is approved. On a newer casita, ask for a copy of the recorded restriction. On an older one, ask the city what applies.

An ADU is different. The ordinance defines it as a subordinate, self-contained dwelling unit on the same lot as a larger main home, with its own sleeping, kitchen and sanitary facilities, and it is not a guest house. The city's ADU fact sheet says Scottsdale has allowed ADUs since January 1, 2025, that an ADU needs separate access, its own address and its own electric meter, and that it can be rented separately but can't be sold separately from the main home. The City Council amended the ordinance on September 30, 2025, according to the city's October 6, 2025 news release, so an older summary may be out of date. The city's ADU page lists the size limits, so check the current page.

The Scottsdale Revised Code, current through its June 10, 2026 update, doesn't say whether a guest house may have a kitchen. The guest house definition says only that a guest house is not a dwelling unit, and the four conditions on guest houses in the zoning ordinance cover size, utilities, rental and setbacks and never mention a kitchen. The word kitchen shows up in the ordinance's definitions of a dwelling unit and an ADU, which is why a casita with a full kitchen is a question for the city's Planning and Development Services. I would get the answer in writing before you count on it.

On renting, the ordinance and the city's page agree that a guest house can't be rented separately from the main home. The city says it can be rented only together with the main home to the same person or persons. A separate tenant in the casita is an ADU arrangement, and according to the city's ADU fact sheet, an existing guest house can be converted to an ADU if the owner shows it meets the ADU requirements and receives approval. The same fact sheet says older ADUs are not grandfathered, and that a unit has to meet the current requirements and be approved before it operates legally as an ADU.

Start with the city's Property Information Request tool. It takes a street address or an Assessor's Parcel Number and returns the zoning plus links to permits and other property records. The city's Building Permit Search lets you view permit details and permit documents, including certificates of occupancy, and you can search by permit number, street name, lot number or APN. The city's own tool says its information should not be relied on without proper field verification, so I treat it as a starting point.

If the address or parcel number doesn't come up, the city's Planning and Development Records office is at 7447 E. Indian School Road, and its page lists 480-312-2356. The city's guest house page says plans go through permit review before a guest house permit is issued, and its permit services page says a permit is required for additions and accessory buildings, with a lighter site plan review for storage buildings of 200 square feet or less. Ask the seller for the permit numbers, the final sign-off and any plans, and ask whether the square footage in the listing includes the guest house.

The seller's disclosure is another place to look. I walk through what Arizona's form asks in my post on seller disclosure when selling a house in Arizona. Use your inspection period to have the casita's electrical, plumbing and air conditioning looked at on their own, because a separate building can have its own systems.

According to the City of Scottsdale's permit services page, work completed without a permit is fined an amount equal to double the permit fee, so an unpermitted casita can bring a cost and a corrective process that the seller may or may not have dealt with. Check that page for the current wording. What it means for a particular house is a question for the city, a licensed Arizona attorney and your title company, because I don't give legal advice.

Lenders react too. Fannie Mae's Selling Guide says that when an appraiser finds an addition without the required permit, the appraiser must comment on the quality and appearance of the work and its impact, if any, on the market value of the property. Ask your lender early, before the appraisal, how it handles a structure with no permit on file.

According to Fannie Mae's Selling Guide, a detached structure with finished area is reported on a different line in the appraisal's adjustment grid and is not counted in the subject's reported finished area. For an ADU, the guide says the living area is not included in the finished above-grade square footage of the main home and is reported and adjusted on a separate line, unless the ADU is part of the main home with interior access. A standalone structure that doesn't meet the ADU minimums is treated as an ancillary structure, with its own line and an adjustment based on its contribution to value, so a casita can add real value to an appraisal while not adding to the main home's square footage.

The same guide sets the minimums. An ADU needs its own entrance, kitchen, sleeping area and bathroom, and the kitchen needs cabinets, a countertop, a sink with running water, and a stove or a stove hookup.

The guide also says only one ADU is permitted on the parcel of a one-unit home, while the city allows one attached and one detached ADU and a third on a lot of one acre or more if one is an affordable unit, so a lot with more than one ADU is something to take to your lender first. The guide describes Fannie Mae's rules and each lender can add its own, so ask yours how the appraiser will report the casita and whether the listing's square footage counts it.

Under A.R.S. 9-500.39, an Arizona city can't prohibit short-term rentals, but it can require a local license, apply its zoning and safety rules the same way it does to other property, and, for a property with an ADU that received final approval on or after September 14, 2024, require the owner to live there. Lawmakers have been changing this statute in 2026, so check the current text. According to the City of Scottsdale, an owner renting for less than 30 days needs a Transaction Privilege (Sales) Tax license from the Arizona Department of Revenue, and the city's short-term rental page lists what else applies.

For a guest house, Scottsdale's own rule is narrower. The city says a guest house can be used as a vacation or short-term rental only if it is rented together with the main home to the same person or persons. For an ADU used as a short-term rental, the city's ADU fact sheet says the owner has to live on the property, and the city's ADU page caps occupancy of the main home and any ADUs on the lot at six adults in total. Here's my post on buying a second home in Scottsdale, which covers short-term rentals more broadly.

A casita with a full kitchen, a separate entrance and its own electric meter raises three questions at once, and all three come from the city's own rules. The ordinance says a guest house can't be separately metered, while the city's ADU fact sheet says an ADU must have separately metered electric service and separate access. So a casita on its own meter is a question for the city about what it has on record.

I would ask the seller for the permit and any ADU approval, ask the city whether the structure is recorded as a guest house or an ADU, and ask the lender how it will treat the casita if it is an ADU. If the answer is that it was built as a guest house and later given a kitchen and a meter, the city's ADU fact sheet says an existing guest house can become an ADU only with approval. A licensed Arizona attorney can tell you what that means for your offer.

Location matters too. According to the city's ADU page, a 2024 state law (HB2720) restricted ADUs near airports, a newer law reduced the size of those restriction areas, and parts of Scottsdale are still within the operating vicinity of Scottsdale Airport and Phoenix Sky Harbor. ABC15 reported that state lawmakers questioned how Scottsdale applied those airport limits to casitas. If the lot is anywhere near an airport, ask the city whether it falls in a restricted area before you count on an ADU.

The city's October 2025 news release says HOA rules may be more restrictive than the city ordinance, and your community's CC&Rs control what you can do with a casita, whether that means rentals, size, appearance or who can stay in it. Arizona's resale statutes, A.R.S. 33-1806 for planned communities and A.R.S. 33-1260 for condominiums, require the association's bylaws, rules and declaration to be delivered to the buyer. Where a community has fewer than 50 properties, the owner delivers them within ten days after the offer is accepted, and where it has 50 or more, the owner gives the association written notice and the association has ten days to deliver them. Read them for casita, guest and rental language. My post on HOA rules and regulations in Arizona goes through what to look for.

I can't give you property tax or insurance numbers for a casita, so these are questions to ask. Ask the seller whether the county's record of the home includes the guest house, and ask your insurance agent whether the policy covers the casita as part of the home or needs separate coverage, and whether rent from a guest or tenant changes anything.

• Counting the casita's square footage as home value. The listing may include it, while the appraiser reports it on a separate line. Ask your lender before the appraisal.
• Assuming it can be rented to a tenant. A guest house can't be rented separately from the main home, and only an ADU can.
• Trusting the listing words. Casita and guest quarters aren't the city's terms, so ask which one the city has on record.
• Skipping the permit check. The city's search tools take an address or parcel number, and they take a few minutes.
• Reading the HOA documents last. The CC&Rs may be stricter than the city.

Tell me the address, and I'll pull the zoning and permit records the city shows, ask the listing agent for the permits and the recorded deed restriction if the casita is newer, and flag what to take to the city and your lender before your inspection period ends. Here's how buying works in Arizona, step by step. Get in touch or call me at (480) 203-6605.