I'll give a stab at this..
If you are building on the Earth and not the moon,
1. Research the company selling the lot. Do they have any developments you can look at to get an idea of how they perform and if the homes hold value.
2. Are there limitations on who you can select to build?
3. What are the utilities? Are you tied into a private water supply?
4. Will they allow any construction that would adversely affect your home value?
5. What other developments are in the area?
6. Anything in the area that is a negative?
7. How are the schools? Taxes?