But if you guess the highest and tie with someone else, nobody gets the bonus? For example I guess 20,000 and so does someone else, neither of us gets the bonus, and therefore have nothing left to guess in the next round, and be eliminated?

Also, after round 1, someone may have more left than anyone else, and be able to guess their maximum and be gauranteed a bonus for another round of guessing?

It sounds interesting. It doesnt sound like there really can be too many people, but it may take quite awhile anyway.