Here are some typical seller closing costs (besides commissions):
Title insurance (which varies from place to place, property to property)
Closing Fee (here in CO it's about $300, typically split 50/50 between buyer & seller)
Prorated amounts for taxes, HOA dues, water/sewer, etc.
Seller Concessions (aka Buyer's closing costs that the buyer is asking the seller to pay)
And of course their loan payoff amount.
Hope this helps!