It's a given on an estate pipe that they are used. A well cared for pipe gets better with use and it is an economical way to grow your collection. Pay attention to descriptions and check out vendors. Look around at other auctions and get a feel for what similar pipes are going for. If you buy from a dealer they are usually sanitized. If you don't trust that, you can always pour some 151 proof rum through them. It will sweeten and sanitize the pipe. Soak the mouthpiece in a bleach water solution. Some people get more elaborate. If you are really curious about sanitizing a pipe, just do a search for it. There are articles out there about it.