Many of the properties that border the preserve are very expensive. Think, "I have an Arizona Cardinal Football player as my neighbor, " expensive.
For example, there's a listing for $2.9M, which has 6000 sq ft. Nice house.
However, there are a few homes that might fit the more "affordable" bill in Ahwatukee in the $225 to $300 per square foot range. A bit depends on what specifically you mean by a hillsidehome, and how far back in the "big cul-de-sac" you are willing to live.
Give me a jingle, maybe my listing in Ahwatukee might even work for you. It's less than 1/2 mile from preserve trail access.