ADU/Granny Flat ROI Kalkulator

Imagine having a little extra space on your property that could actually earn you money or give your family some much-needed breathing room! That's exactly what an ADU, or Accessory Dwelling Unit, is all about. Think of it as a 'granny flat,' an 'in-law suite,' a 'backyard cottage,' or even a cleverly converted garage – it's a secondary home on your existing property. With housing getting tighter and families often needing flexible living solutions, ADUs have become super popular. This calculator is your personal financial crystal ball for figuring out if building one makes good financial sense for *you*.

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1. 1It's super easy to get started with our ADU ROI Calculator! Just follow these friendly steps:
2. 2Step 1 — Tell us your total build cost: This is the big number – everything from getting plans drawn up to the final coat of paint. Don't forget those 'behind-the-scenes' costs like permits and utility hookups!
3. 3Step 2 — Estimate your monthly rent: Do a little detective work! Check out what similar places are renting for in your area. Websites like Zillow Rentals or Apartment List are great for this. Input what you think your ADU could realistically fetch each month.
4. 4Step 3 — Factor in your monthly expenses: This is where you tally up all those regular costs. Think about any extra property taxes, insurance, a little bit for maintenance (things *will* need fixing!), and a small buffer for when it might be vacant. If you're hiring a property manager, include their fee too!
5. 5Step 4 — Guess your property's appreciation rate: How much do homes in your area typically go up in value each year? A general range for many places is 3-5%, but you can adjust based on local trends. This helps us see the long-term value.
6. 6Step 5 — Let the calculator do its magic! It will quickly crunch the numbers to show you your **annual net income** (that's how much money you actually keep after expenses, over a whole year).
7. 7Step 6 — See your cash-on-cash yield: This cool number tells you, in a percentage, how much money you're making on your initial investment each year. It's a key indicator of how financially smart your ADU project is!
8. 8Step 7 — Get a 10-year outlook: Finally, the calculator projects your total financial picture over a decade, combining all that rental income with the expected increase in your property's value. This helps you see the big, long-term payoff!

• !Forgetting all the 'behind-the-scenes' costs: It's easy to budget for lumber and labor, but don't forget those 'soft costs' like architectural plans, engineering reports, permit fees, and getting utilities (water, sewer, electricity) hooked up. These can easily add 15-25% to your budget, so always factor them in!
• !Getting a surprise property tax bill: Many people forget that adding an ADU will likely increase your property taxes. This isn't just a one-time fee; it's an ongoing monthly expense! Always call your local tax assessor's office to understand exactly how your taxes will change before you commit.
• !Building a palace when the market wants a cottage: It's tempting to put in all the fancy finishes, but if the going rate for a rental in your area only supports a mid-tier unit, you might be overspending. Make sure your build cost and finishes align with what tenants are actually willing to pay in your specific market.
• !Underestimating your own time if you self-manage: If you plan to manage the rental yourself, that's great! But remember your time is valuable. Factor in the hours you'll spend dealing with tenants, maintenance, and showings. Sometimes, a property manager's fee (8-12% of rent) is worth it for your peace of mind and time savings.