The first cost to you will be 1.78% of the selling price as excise tax to the state. After that a Title Insurance Policy, prices vary depending on the company and level of coverage, check with the company you used when you purchased for a starting place and then 1/2 the escrow fees. Again, the cost of escrow can vary so check with local companies. Many Title & Escrow companies can provide some discounts for using the same company for both services. There may be other minor fees but these are the biggest.
Now that I've answered your question as directly as possible, not knowing where to start with these issues is a sign you may not be prepared to know many other issues that you should in order to successfully sell your home without professional assistance.
A great agent is worth more than they get paid, but a bad one or none at all can cost way more than just a commission. Find a great agent and you won't be disappointed.