What is a fair acquisition % fee in this scenario?

[Kurt Beadling]

My brother found a 4 unit multifamily house that was listed way too high at $525k initially. They listing had a failed pending sale and eventually my brother talked them down to $400k sales price planning to buy it on his own. He couldnt get the mortgage he wanted and needed help with the down payment from me, so we formed an LLC to buy the house with each of us investing 50-50 equally on the down payment.

He did all the work finding this deal and negotiating the great price so I agree he is entitled to some sort of acquisition % fee. He proposed 2% which would be $8,000, does this seem fair or standard? Should the fact that I only own 50% of it change this fee since he is a 50% owner of the deal also?

First time encountering this scenario so I appreciate any advice