To make addon you can do only in late game - in specific period of time.
I always do addon, if i will win guaranteed money with profit. For example
left 70 players paid 20 places, 20. - $6, but addon $1, i will do addon, because $4 profit. Ofcourse its depending from my stack. If i am first or 10 place, i will not do addon.
I think you should look on how much BB you have, if you have 50 BB i think you can play without addon, but if 20 less, then you can easy do addon, its my personal opinion.