It might be a good idea to get a certified antique appraiser, actually several different ones. They will tell you what the items are worth and what they charge to hold an estate sale. Remember, one man's trash is another man's treasure. You may have things that you are not aware have value.
It depends on what is left in the house. For misc. items you can schedule an appointment with Nice as New or any of the other consignment stores in town. Craigs List always work well for us when we come larger items of value..ie appliances and furniture. If you are wanting one company to handle everything, you can always hire the services of an auctioneer. There are a few listed in the local yellow pages. If you have antiques or collectable and antique dealer might be a good first call. Once again there are several listed in the yellow pages. I hope this helps.