Free,

As state commissions are completely negotiable...check around....there's no such thing as a "normal" or "going" rate...get the opinion of some other agents in your area. I've worked with a few in Lenawee County before if you'd like a 2nd opinion I'm happy to pass their names along.

Commission rates are negotiable. This rate does seem quite high for the area, but the agent may be suggesting that you offer a higher buyer's commission to incent agents to show and sell the property. Depending on the characteristics of the property, s/he may feel that the vacant land merits the higher commission because it will take longer to sell. If you're not comfortable, talk to someone else.