Ok here goes for free:
http://www.craigslist.com (search similar number of rooms, with keyword = zip code or community name)
I want to stress that in many years of renting (my own) properties I have never found a renter from the mls. I have found them from craigslist.com, and before craigslist, from ads in the arizona republic- which were expensive.
I'm a professional property manager. As part of the listing process I naturally do rental comparables. If you are interested in using a property manager to rent your townhouse, I'd be happy to help you with comparables.
FYI, although using an appraiser for such a thing would be effective, and potentially very comprehensive...it would also be very expensive. Typical appraisal fees are very close to the entire commission I charge to rent the home for a year, which INCLUDE my estimate of rental rates...and from someone that has successfully rented 40 homes this year alone.
FYI, the hassle with craigslist (and I wouldn't ignore craigslist), is that it's not a very location specific search. If there are listings in your townhome community, you will probably find them, but what about the next community over, or down the street, or around the corner. It's brutal (not impossible, but tedious) to use craigslist to find rental comparables for homes within a mile or two, which is part of what you want in the analysis. Also, you never know what it actually rented for, just what the asking price was.
Have you found a qualified Realtor to help you with your rental home?
West USA Realty
Can't you just ask a local realtor?
Usually our estimates are free, no obligation.
btw, you mentioned that your property is close to a college~~ usually such neighborhood offers many properties for rent. Check local media. Good luck!
A rental management company may be one source or an agent could let you know how many are available on mls in that area.
It sounds like you have a nice town home. You should be able to rent it if the rent isnt too high.
Feel free to contact me if you have any questions or would like any more assitance!
You can also call a local realtor to help you if you are not physically around. e.g. Melisa just told me that she has investor from FL coming to Edison NJ and she helped him to buy and rent out the condo at Starpoint at Piscataway http://starpointatpiscataway.blogspot.com/
On the other hand, the investor Michael also told me that he placed free ads from FL thru craigslist.org to help Melisa... It is a team work these days to reach the most cost effective result.
From this address: http:findahouseaz.com you can search for rentals in a particular area (zip code) and see what comes up. If you would like more help or me to send you some comps I would be happy to.