It's somewhat ironic that I, being a tax professional, insist on pushing taxes into a secondary role, but I do.

But if they insist on paying a percentage, then it depends on if the GC is paying for everything?

The new equity of 80k is now buying you a property worth only 2.3/dollar of equity....and, it's still not your money.Sell the property and it becomes your money, and if you insist on paying 30% (DP) of the PV, you are now buying a property worth $242k+ 

Admittedly he insisted on paying for some of the material upgrades & it was worthwhile.

Now you're locked into him for a while....I would send him an email (so you have a better record) and insist that he respond within 48 hours.

Using Minut (great for noise monitoring but undecided on cigarette-smoking as the 3 sets of guests it called out- 2 were iffy/possible and 1 insists no smoking but they grilled so more testing is in order still).

I will definitely try this, and I usually escalate with anything else if needed to but never thought to do it for realtors as well after they insist having my agent call them to see the property.

Should I insist he put skin in the game up front as well and we both take our chances on losing money?

The lender insists on paying the proceeds or the cash-out amount to the LLC and not to the friend's personal account.

Quote from @Jami Lynn:  If the seller is one of the "recognized" "minorities" (that's who've we always had problems with later) we insist they bring along a family member or best friend "to help celebrate" (be a witness) and we get them on video too of course.