The best way to value a home is to look at how many homes are on the market currently, close by, that have relatively the same specs (beds/baths/etc.). I normally go about a mile out in radius unless it is downtown Denver, then it is more like 5 or 6 blocks. From there you need to know about the finishes and upgrades that each of the homes have, so you can determine the order in which they will sell (price doesn't matter yet). From there, look at how quickly homes that are comparable to the subject property are selling. So here's the example:
Subject is property A. A has 3 comparables: B, C, D. They are all 2Bed/1Bath homes. B is listed at $110K, C is listed at $105K, and D is listed at $120K. You tour the properties, and determine that B has the best finishes and layout, D is second, and C is third (A would be second if considered). You look up how long it is taking 2B/1B homes to sell in the area, and determine that it is 60 days. If you want the home to sell first, it will need to be priced at $109K, or in that area.
I know that doesn't exactly answer your question, but value is determined by the market, and it is constantly changing. This is the way that I price homes, and it works fairly well for me.