Marketing for homes in a competitive city

[Dave Vona]

Hi, I'm looking to start flipping homes in Denver.  I'm working with a partner and our initial plan is to buy homes from wholesalers.  Once we generate some profit, I'd like to try putting that into marketing directly to home owners.  I know there are a number of lists and approaches to direct marketing and you need to remain consistent with one or two methods to start.  I was wondering how to gauge which lists are going to be effective in a competitive market like Denver.  It seems you could go broke if you had to try every list for 6 months first to see if it was returning any deals.  Does anyone have any suggestions for how to find which marketing approach is going to be most cost effective in my area?  Thanks.