I think a great tip is to have some kind of check at the end of solving the puzzle that lets them know it's solved and solved right. I've done a few multi caches that had you count things and plug those into the final digits of the coordinates.....problem was that if you miscounted or had a difference of opinion on what constitues 'in front of' you'd be off on a wild goose chase and know it.....best to have some kind of 'check sum'.
r/
The Beys