I am by no means an expert at "finding the reasonable paying customers" but my first suggestion I use to qualify peoples need for an estimate is a charge for the estimate. I generally subtract the price of my estimate fee from the work when the work is completed with in 30 days. I have found it helps two fold: 1. If they balk at the price for an estimate they are usually price shopping and won't have the work done. 2. The 30 day limit helps with people calling years later wanting the estimated price. If it's like 2 months later or something like that (within reasons) I'll usually do the work.
Bear in mind though my business is mostly referral as I am a one man band.
Bear in mind though my business is mostly referral as I am a one man band.