first off, nothing is bulletproof. If you expect to have crashes and rollovers and failed jumps, you will need to replace parts.
Truggies are tough, they're meant to be. The more you spend, the better you will get. If I was to start over, I would start with a truggy. I have way too much invested in maxxes to switch.
Your best bet for the money would be to put a brushless powerplant in your revo, and upgrade as needed.
You'll get a million different opinions on this subject. No matter what you get if you drive hard, you will break.
IMO the LST is the strongest monster truck, maybe someone else will post what they think the best buggy and truggy are.
If you're looking to save money find a different hobby