Repairs. You will want your house to look its best to buyers. That may require you to get any needed repairs done before listing. You don't want a buyer to see a dent in the wall or a dripping faucet.
Renovations. It might make sense to get a few improvements done to make the house more attractive. For example, you may want to replace old and work kitchen countertops.
Legal fees. Selling a house requires a lot of legal work. You'll need a good real estate lawyer to take care of that for you.
Commissions. This is usually calculated as a percentage of the sale price.
Moving costs. Once you sell, you'll obviously need to move! So, factoring in this expense is a smart idea.