They will barely talk to us and are being completely unreasonable.

You go ahead and forego a months rent for the small town you operate in to accommodate unreasonable requests, if this is how poorly you manage I pity the people who crowd fund with you and your partner.

If people behave unreasonably, you just have to stay with the law and do things the right way.

In a more normal market like we are in now I would say they at least need to pay your PITI, so you're made even...and I would charges some daily amount of rent, even if small, and jump it up to something unreasonable if they stay over.#4 the one nice thing if you lease back to them is that you should get a deposit and rent credited to you at closing.Good luck.

Why is it unreasonable to ask the same of people transacting tens or hundreds of thousands of dollars?

I agree with @Jim Piper that if this is to be an ongoing relationship it is especially important that you make a stand and not allow this person to dictate unreasonable terms to you.

Seller says the closing date should have been set a day or two after and is insisting on an unreasonable daily fee to cover his carry ($90/day, so a little less than $1000).

(B) If the landlord makes an entry in violation of division (A)(8) of this section, makes a lawful entry in an unreasonable manner, or makes repeated demands for entry otherwise lawful that have the effect of harassing the tenant, the tenant may recover actual damages resulting from the entry or demands, obtain injunctive relief to prevent the recurrence of the conduct, and obtain a judgment for reasonable attorney's fees, or may terminate the rental agreement.

We have often tried not to pay this or asked for the buyer to pay it and the agents all get really hissy about it.So looking at the bigger picture if we're getting deducted around $20k in closing costs per deal and 6% agent fees on  this is $1200 which seems to be unreasonable because this is money other people are getting and we're effectively being charged fees on funds we never even get to touch.Most banks for example do their closings "Commissions paid net of closing costs" which means they won't pay any commission on money they don't get at closings. 

Is that too unreasonable, or do I need to really compress it, somehow?