I played live for the first time this weekend! Turned out a casino nearby is actually running Pot Limit Hold'em, Stakes 5/10 (Euros). Minimum buyin is 250, maximum is unlimited.

Now my question is, what is the ideal buyin for me given the following setup:

6-7 fish and/or predictable players with a stack of 50-60 bb on average, some 100bb if they doubled up
2 regulars, LAGtards, with a stack of 200 bb +

What is my best buyin

a) 25 bb (minimum)
b) 50 bb
c) 100 bb
d) 200 bb+ to match the regulars

?

I play a tight-aggressive game

I think 1000 should be fine (100bb). I'd be preparred to rebuy at least once (if you clearly have the best of it, but lost under acceptable conditions -- ie set over set or suckouts)

I'd normally say d) 200BB's but here it is your first live game so I'd err on the side of caution and go with 100.

Definitely cover all fish, and don't bother match players who are at least as good as you and probably more used to a live setting. As you say they are not where your profit is coming from, and playing shorter buy in will allow you to get more value from your premium hands against the better players by denying them implied odds.

If all the fish have 50bb I would literally buy in with 50bb and top up to 100bb when a couple of them have doubled up and have 100bb stacks.