Trust is first thing you need. Good thing about being in Houston is Sean Cody. He did my trust over the phone and is great to work with.
Secondly, buy the silencer. Look no further than Silencer Shop. You can have them mail it to you or you can pick it up on the store in Austin.
Always buy a silencer that is IN STOCK. The genesis of many issues with NFA toys happens when you buy something not in stock. Reason being is the paper work. Your dealer may be getting it from a distributer and that distributer may need to get it from the manufacturer. That is two form 3s right there and 4 months worth of waiting before you can start your form 4 which takes 3/4 months.
Other costs involved are QD mounts if you are getting a QD silencer and of course Uncle Sam's little tax stamp ($200).