Thornton to Erie is a pretty big stretch. If he'll need to be driving on I-25 to commute, you'll probably want to be as close to the job location as possible...that stretch of highway gets clogged up pretty badly.

I'd also say to look for a realtor - the lady I bought my house from manages properties as well as selling them. She doesn't have any in that area though (she tends to specialize more in the furnished student apartment area)