Definitely expensive. I'm very cautious about the events I enter because of how expensive they are. I feel like I'm taking a big risk entering StG because the course is probably the most challenging course for me. I allowed myself to be talked into it but I feel I am as well prepared as I can be, definitely better prepared than I was for IW a couple years ago. I learned from IW and from IMAZ, so I think that's going to help me. Even so, I know I'm going to be bumping right up against my physical limitations as is, not a big margin for error.
As for the equipment, I put good money into the bike and into my run shoes. The other stuff, I hunt for bargains. I buy used wet suits. I do have a few tri suits but only two bought new. Three others were gifted to me by a member here a while back. I've even run across a couple in a Goodwill store. I didn't buy them because I already had what I needed, but you can, on occasion, run across deals through Craigslist, garage sales, thrift stores, etc.
The point is, you really have to figure out where your money is best spent. For me, it's bike and shoes. All the other stuff is kind of superfluous. I mean, I need it, but a $100 pair of goggles is not going to make me faster on the swim than a $30 pair.