Tennessee has a very low cost of living. The housing market is low cost and its value has remained fairly constant. The city, county, and realestate taxes are some of the lowest in the nation. The state does not have an income tax.
One of the lowest cost of living states is Kansas or Nebraska. This is because there is nothing to do there and it can be a lot of farm land. Any state with a lot of farm land that is not near a coast has a low cost of living.