Isn't it expensive to play USAV?

The level of expense is really dependent on what you want to do.  If you plan on practicing a few times a week, having a professional level uniform, warm up outfits, matching shoes, etc? Then yes - it can get expensive.

On the most cost effective side, there's a few ways to do it.

#1. You need a uniform.  I'll post more information about the uniform later, but the basic crux of it is that you need a shirt with a number on front and back and shorts.  The entire team needs to be wearing the same uniform. Shoes and socks are irrelevant.  You can probably get these, on the cheap side, for around $30 per person.  This is a one time expense.

#2. You need to sign up for a USAV membership. This is $30 and must be paid annually to the USAV region.  This covers such things as extra insurance and region costs.

#3. You need to show up at tournaments.  This costs $115 / team, so a team of 8 players just pays $15 per person per tournament.

That's the basic cost involved.  If you attend each of the Austin tournaments from September through March (about 6 of them), you've paid $150 for the season.

Some teams take it to the next level and require dues to pay for gym space for team practices; others play in leagues and yet others, I'm sure, do things differently from that.  I'll go into some of these other options later.