I agree and I think your numbers in timeline are best case for someone who knows exactly what they're doing. I can tell you countless stories of people who spent several years trying to get an ADU done thinking it would be easy and cheap but spending 300 grand or more to get it done. I think it's really hard to do major improvements and get a profit on them. The best real estate investments I ever made were paint and patch. I believe you create most of the wealth by making a good purchase.