What permits did you need?
The cost of everything, and size?
Biggest hassle?
My house is about to be payed off, and I was thinking of investing in one for extra income.
In my area (USA) this is called an 'auxillarly dwelling unit' and only permitted for new construction on lots larger than 1 acre (or renovations to an existing structure)
>>1235141
Op
I also stay in the USA, California. The property isn't an acre. Has a good amount of land to build something smallish tho, like a one bedroom unit with kitchen and bath. Building and safety department would be a good start of finding out right if possible?
>>1235144
The whole "tiny-house" idea is usually based on putting them on wheels of a big trailer so you can avoid these minimum living space rules by calling it an RV.
It's pretty overrated, IMO, because you could just buy a used travel trailer for much less money and no effort.
But sure, all you need to do is email your local building inspector office, and ask. These rules are often town-ship based so who knows?