Broker's Opinion of Value: Can I get before I put under contract?

[Matt Fisher]

I recently got a call from a fellow who inherited a rural property close to the Des Moines Metro Area.  Although I know the area very well (I bowhunt right across the street), I don't have a good estimate of value for rural acreages here.  I have a sense it's worth about $200k and I could probably get it for $140-so it would be a good deal-IF I can resell it.

What I would like to do is get a broker's opinion of value before I get it locked into a contract.  This seems like a fast way to get a better understanding of the value and gives me something more tangible to talk with my banker about. 

Is this ill advised?  I guess I'm just being cagey about the lead...  I welcome any thoughts about other ways to proceed.

Regards,
Matt