Hi Will!
Nice post. As a new wholesaler myself, I'd like to add my 2 cents. I would venture to say the responsibility of due diligence resides with both the wholesaler and the buyer. Any seasoned investor should know not to take a wholesaler's estimation of repair costs or ARV at face value. Questions would naturally need to be asked including "how did you come up with those figures"! The same goes for ARV, one should be asking where this came from. Any wholesaler worth their salt certainly has a partner realtor who provided them with actual comps that you could request a copy of.
Also, a simple google maps street view will show you if a property is undesirably close to a freeway, etc, which would save you a trip to a property you likely will not have interest in. I disagree that to be a good wholesaler you must be an expert at estimating rehab costs, but if one is not, they certainly should have good contractor partners that can accurately price out repairs and/or rehab costs before they market a deal. I definitely agree with your other 2 "ingredients".
Ultimately, in my opinion a good wholesaler will have the right business partners and adequate knowledge already in place to provide true and accurate figures to potential buyers. They will also be able to easily answer the question of how they obtained their figures and produce documentation if needed, with a goal of respecting their buyer's time and creating the best mutual win. However, as a serious buyer who values his/her time and money, asking important questions to vet the deal presented to you should be a part of the regular method of operations.
