The most that I have experienced is that my bet was multiplied around 20 times. It was in the lottery, so the chances that I had was pretty low. If you manage to bet in a lottery, you have to have at least around 4 numbers to have a price because for three you only get your bet amount. The lottery would still be one of the largest wins that you could get.
I believe from dice and roulette games we can get maximum rewards when compared to casino and sport betting,I didn't made any big amount which is considered to be as maximum reward in single bet but when I calculate the average most winning rewards the it will be the sport betting I think.
Well, I guess you could just estimate how much you have won in something, that's not going to stop you in my opinion. Probably, you don't remember it because it wasn't that much of a win to you because of the prize you won. I guess you are really lucky choosing the teams who win or lose. That's a great skill.