Nitram,
All this usually depends on the site and the tournament. Some will be unlimited rebuys when you are less than the starting chip count or some will be one rebuy. Say if you started with 1500 and get down to 1480 after the first blinds. You can rebuy at that point at some of these tournaments.
Now an addon is done at the beginning of the first break. I know at Jetset, if you have less than 10,000 chips at that time you can rebuy for that certain price and get 2000 on some tournaments.
There are even some
freerolls that allow you to rebuy for a $1.00 or whatever that set price. Infact Cardschat used to have some freerolls like this in the past.
I know somewhere on here there is a guide to rebuys/addons. But this is how I play them.
I play tight aggressive the first hour, especially if it is unlimited rebuys. If I get in a hand it has to be a strong one. If I lose and I am short stacked I will rebuy, but usually only once. I let the others take each other out if I can. I have made it to the money and final table a time or two with just the addon and no rebuys.
When the addon/Break period starts, I look at the chip counts and my stack, how many are still in it and what the money looks like. Most sites will show how many rebuys and addons have been done already. But they won't have a final payout ready yet till after that period. I will usually addon if it is beneficial enough to my stack and may even pull me up in the standings at that point.
After the break/addon period many players tighten up so much they squeek!!! Which I still do a bit but I take a few more chances of stealing blinds and pots.
I, myself don't play these unless there is a guaranteed payout to begin with.
I used to hate these kind of tournaments. But I am starting to get used to them. I still don't love them, but they are growing on me. But I also don't play high buyins either. Just the low roller tournaments of a buck or two.
I hope this was helpful