can trap be re used after catching a mouse or is it truely only good for 1 use?

They just want you to buy more. These are 100% reusable.

These are definitely re-usable. Tomcat's offical answer is basically "mice are icky; you don't want to touch anything they've been on" which is a fine answer, but the traps are VERY re-usable. I use nitrile gloves and give the trap a quick rinse on the outside hose before I put it out again.

It is recommended not to reuse a trap. Use convenient grab tab to dispose, then replace spent trap with a new mouse trap.