He gave a different name from that phone number. If he/she doesnt meet you face to face DO NOT take anything down!
And yes its a scam for two reasons. Told me he/she moved TO IOWA. Listings for same house we were about to rent (ann arbor, mi) were the higher than the one sent by same phone number as posted here.

Contacted the REAL realtor and said the house was already rented and the guy still kept wondering if we were going to rent. Also said only way to see the house is looking through the window. Not to mention the owner "has the keys" and realtor does not. In reality the realtor has the keys.

If you are selling your house/renting, go through verified realtors ONLY! Never ever go through private party to sell. Never take down a sign until you receive the minimum due. If you agree for example, to hold the house for 30 days and the minimum is $100, have a contract specifiying that if the rest of the money is not received by that date on the contract that the house is to be relisted and any finances paid will be forfeited.