Equity Broker Fee for Co GP?

I currently dont have the net worth/liquidity to sign on loans for the deals I'm closing and would like to bring in a co-gp. I have a broker making these connections and I'm struggling to determine suitable compensation for this work. The co-gp may not even contribute any equity and may only be signing as a guarantor for nonrecourse loans, and if they were to contribute equity it would be a small amount anyway so a % of the equity as a flat fee doesn't make sense. In this scenario I'm considering paying a % of my promote to the broker. Does this make sense to you, and if so what % would you pay? Or, is there an alternative structure that works better? A general flat fee? Need some input here.