Mostly to buy down rate, and make payments more affordable for 1-2-3 years for the buyer–until they can hopefully refi at a better rate and get more cash-flow with their LTR/STR investments.I just accepted an offer on one of my properties today that asked for 3% concessions.

Even if your units are in great condition, most residents won't be able to afford a $200/mo increase in rent. 

DEFAULTS Tenant will be in default if: (A) the Tenant don’t timely pay rent or other fees and charges they owe; (B) Tenant or any guest or occupant violates this Lease, property rules, or fire, safety, health, or criminal laws, regardless of whether or where arrest or conviction occurs; (C) Tenant abandon the property; ....When Tenant is in default, the Landlord has the option to declare the entire balance (all outstanding balances including but not limited to invoices, rent, cost due to damages/abandoning the property) payable hereunder to be immediately due and payable; the Landlord may exercise any and all rights and remedies available to Landlord at law or in equity and may immediately terminate this Agreement.XVI.

The homes are affordable.

What are you referring to when you say more affordable housing?  

I have been very high on the potential of Eugene for continued and rapid investment growth and opportunity for a variety of reasons, and have likened it to a more affordable Boulder..These very well paid athletes and the entire ecosystem built around them..ie: brands, influencers, media, boosters, coaches, alumni, all need to be accommodated.

More often than not, we get a flipper who does the work themselves, has cash, and can afford to pay more than others.

I wish you great health and happiness. 

I imagine most buyers who request the seller cover their buyer broker fee are those that can't really afford to pay it so wouldn't be able to pay an appraisal gap.  

I think there is a chance that you don't actually hate your rentals, but rather, you hate where your mental health/stress level/amount of free time is.