The negotiations were quite difficult to find the terms that worked for both parties.

Forgot, if you get a 3rd party doing the billing, make sure they do collections also. 

But you also are required to use the services of a 3rd party called the qualified intermediary that he refers to. 

We had an STR down the street from me that specialized in holding bachelor parties.

Standard practice and the veriage should prohibit the person from doing any deals directly with the parties you are in negotiation with. 

The important part is ensuring you have the ability to refinance when a balloon comes due.

Have they ever been counsel to a party who was sued and lost everything personally due to real estate ?

This means that the seller will defend and protect buyer against right claims of third parties to the property (warranty of title) and no liens or encumbrances in the property (warranty against liens and other encumbrances) exists except on the items listed in the deed.

My approach is two fold:- Gently keep in mind and remind clients there are two parties and perspectives involved.- Address buyer's concerns with reputable local professional and expert evaluations and written estimates.For example if the deck needs to be repaired or replaced, during the contingency period I'll attempt to have at least 1-2 licensed contractors provide written estimates.

Quote from @Matthew Mueller: I don't know the law in your state, but in my state a copy of every document should be made available to anyone party to the transaction.I would demand a copy.