The $7,500 dollars is going to pay for the buyer's closing costs. For the seller in a scenario like this would have to pay tax stamp of $4.56 per thousand the property sells for and in this situation that would be roughly $1,094. Then you have the deed drafting. Those are the basic seller closing costs. All the best
Seller closing costs are mostly selling commission and many smaller items. If a buyer is ASKING for a closing cost credit the amount can be anything they ask that their bank will approve, but just look at the net number. So a $245K price with $5K in closing costs will feel the same to you as a seller as the $240K. There is a very minimal effect on tax stamps, but we're talking like $15 or so...
Seller closing costs are very minimal. Most would be the 5% RE commission, if applicable. Other than that, very minor- likely less than $1000.
If you'd like more specific information on a deal, please let me know. Thanks, and good luck,