This is a "How long is a piece of string" question. But here are some guidelines:
1. As always location, location, location.
2. If you are thinking long term the public pension deficits of some states make them absolute no-no's. Do not buy in New Jersey, Illinois, Kentucky, Connecticut or Colorado. Missouri is in the middle.
3. Does the property have/will soon have, fiber optic internet, this has become very important in the last couple of years.
4. Will the property appraise if you intend to finance the purchase. Go on Realtor.com/Zillow.com/Trulia to see what similar properties are selling for.
5. Generally speaking inventory is very low in the better states to live in. Builders are very cautious about letting their inventory get ahead of the market. Those that survived 2007/8 are not building spec unless the inventory in their area is very low.
6. Run your numbers on an after tax basis Renting v's Owning
7. Ask the landlord if he will pay a Buyer Broker fee.
8. Interest rates are artificially low, they will go up in the medium term which will dry up a lot of the demand but inflation will hit pretty soon.
Good luck