No. I can buy separate vinyl that could be ironed onto a t-shirt, but that would be more expensive. If you were to win, & the credits were high enough though, I would consider it.
For every 10,000 I add about an inch. So it's usually at least an inch, and then I just add as the credits go up. My vinyl are 12x24, so it could go all the way up to there if the credits were high enough.
Approximately. All my decals are different. It depends on the proportions, & complexity. If it won't print out nicely at that size, I will make it bigger.