The answers will range due in large part to how the transfer (wholesale deal) takes place and the price points.
For instance, if an REO, it is likely not "assignable" so if the buyer of the REO is using a second escrow for a double closing, then they will want a non-refundable deposit so you don't walk away and leave them holding the bag.
If it is assignable, then it all depends on the contract wording that they are taking over, if an inspection period timeline is left over, they still have that.
In other wholesale deals, they are mostly non-refundable deposits to keep you from backing out at the last minute with nothing to lose, that protects the wholesaler.
As for inspections, typically, you as the buyer should do your inspections first, then decide if you want it and at that point, a refundable deposit is not needed, you have already made your choice to purchase the property.