Lindsay, if you have REALLY put offers on over 25 homes, there is a problem! In 30 years I have NEVER had to do that to get one to work!
The problem could be several. Your agent. The price range, the market, your terms.
Additionally, finding a home in move in condition in the $200K price range is tough everywhere so you may want to slack off on that.
To ask for a 6% concession yet raise the price to cover it could be an appraisal problem. Were any of your offers accepted, but didn't work out, or did they all just say NO.
If you like your agent, why don't you ask her or him what they think the problem is? Sometimes they don't want to hurt your feelings by telling you that you are looking for something that doesn't exist, but IF this person has made 25 offers for you and worked for 5 months, they are either very new, or very patient ;-)
Another thing to look at would be bank owned homes by fannie mae. They give seller concessions, they also are easier to deal with since they are not emotional about the house. There are lots of these available in my area right now, not sure about yours but check out http://www.fanniemae.com and look at their homepath financing. If you find a house that is not in move in condition they also have a renovation loan where you can fix it up.
Good luck and let us know how things turn out for you.