There is no way around a rental trailer. If it was a one-way, it would cost hundreds of dollars. If it was returned to the same place (pick up in Columbus and drop off in Columbus), it would be cheap for one day, for that many days it would be expensive.
It would probably cost less to buy a used one, either in MD or in OH, and use it for the purpose and then sell it again.
The cheapest is, of course, borrowing one from a friend.