Bottomline is having a good talk with all parties openly discussing how to handle this in a way all parties can be happy and lessen surprises.Hope it turns into a wonderful opportunity to get better acquainted with your in-laws. 

Best part I live on the beach in FL. 

First mortgage paid off as well as all other parties (attorneys and surplus, etc).

I recommend a thorough risk management survey, preferably by a third-party professional that is trained to spot problems. 

He advised me to consider the offer at $222k, cautioning that we might have to resort to a price reduction if no other parties express interest.

Yes, I understand that part. I

Yes you'd have the 2.5% fee (not interest, though, just a one time fee) but you wouldn't have to go through third parties, buying gold and such. 

In addition, we also can do “self showings” where the interested party gets a one time showing code.

They're lucky one of us doesn't live there, I can just imagine fun things to do to screw with them.Actually, have a big party and invite BP regulars, I can see it now..... :-)

To the seller, it implies there is no chance a lender will pull out at the last minute and jeopardize the deal.Realistically, most wholesale deals are negotiated well in advance, so all parties know where the money is coming from.