finder's fee amount/percentage?

[Max T.]

I would appreciate input from the community here:

I found a deal for an investor friend. He is paying $90,000 for a property that will rent for $1000/month.

He suggested I ask for a finder's fee... Is 10% too much? 

We will be doing a lot of business together in the future. In the past I have secured a small piece of equity (5%) for the finder's service. I also collect a percentage of the gross rents as his property manager. He wants to do the finder's fee this time since he is buying in his own name (as opposed to an LLC as in the past).

I will be the manager for this deal as well.