Fixed Odds betting

How does this all work in practice? I know how you get to the fixed odds page etc, do bet but

1 - What sort of limits are there? Say on a 10/11 sports bet and a 4/1 horse in a handicap (understand on exchange its prolly bigger)
2 - Do they restrict you very quickly?
3 - What sort of amount do they let you win before getting retricted?
4 - Do the winnings count towards your lifetime P/L for PC?
5 - Have they imposed very small limits for people who are up on the exchange betting side of things?
6 - If you win on fixed odds say football and they limit you, does the restriction apply to just football or all fixed odds betting.

Sorry in advance as probably this has been posted before but I haven't been betting since end of April.