I got my start in the real estate business as a wholesaler before I started buying for myself. Personally I always went above an beyond putting together elaborate packages with pictures, getting at lest 2 contractors estimates, I would break down the numbers for flips and for rentals with refi numbers even, I had a realtor running good comps for me and tried to put the deal on a platter. Have never received one complaint and have a lot of repeat buyers.
Unfortunetly good Wholesalers are much like good contractors, or investor friendly realtors, or good tenants. They all have their bad apples! And all must be veted with the appropriate questions. But just like all of the other "professionals" once you find a good couple hang on to them and take care of them and they will keep feeding you.
Vetting questions from my insider perspective? hmmm I would ask 1. Are you direct to seller (no middle men)? I personally dont like more than 2 in the middle. 2. Always ask for original contract as well as the assignment, if they are squirmy with not wanting to let you know what they got the contract for that is a red flag, 3. They should know ARV, BUT if they don't they should tell you up front. There have been times where I came across a property that was out of my area and I had a ball park ARV but did not know the area like the back of my hand. OR maybe I had not even been to the house because it was 2-3 hours away. 4. a detailed interview of them ahead of time testing their knowledge on real estate terms and thought processes, asking what kind of margins they look for etc. a good wholesaler speaks and thinks just like an investor. 5. ask them what kind of marketing they do and how they get their deals. Just off the top of my head those are some of the things I would have asked myself as a current investor and previous wholesaler looking back.