Most sellers only care if you close so you can usually use another form of capital stack other than what is on the agreement, however, the seller can force you to use the originally agreed-upon payment method. 

The code being cited by the inspector is below if you care to bother.Thank you.https://codes.iccsafe.org/content/IPC2021P3/chapter-7-sanitary-drainage#IPC2021P3_Ch07_Sec708 Could you put cleanouts within the interior (is there a basement?)

Can't say what's hardest, too many moving parts but take care of your tenants and build that goodwill, pays off in spades.

My assumption is that there are a lot of bad apples, and very few that actually care about the seller.

Staff often seemed to focus on one requirement at a time, and only moving on to others as each was taken care of, instead of starting them all at the same time.

This is one of the things that @Matthew Irish-Jones mentioned above - be careful about putting #3 on his list above #1 and #2.

The only thing that I really care about is room on the deal.

You can wind up with title issues if you are not careful. 

Highlight features and amenities they care about most.

The GC is a business person who doesn't care about your ARV, LTV, or your budget.