If you're at a shorthanded table of 5 people with opponents who:

1) are almost guaranteed to be worse than you
2) buy-in for the minimum up to 60bbs

Would you buy-in for 60 blinds too or 100, and is it just personal preference there?

How many buy-ins would you keep as a bankroll?
is 3 buy-ins enough? 6? 12?