My question is, when you first go to a FBO, what to check when seeing a
plane that you never flew on. How do I know that this plane is
maintained well?!

A few things come to mind, and they are far from foolproof. But the
first thing I'd evaluate is the FBO. How are the -other- planes? Look
at the squawk sheets - how do squawks get addressed? Talk to the
maintanance people - get a feel for their attitude.

Is this particular plane a leaseback or owned by the FBO? (neither is
in itself good or bad, but it will give a sense as to how much of the
initial feeling carries over to this plane). If it is leased back, talk
to the owner.

Do a thorough preflight, and bring up any concerns. Gauge the response.

Go over the manintanance logs. This of course requires that you know
what you are looking at, which isn't always that easy). Talk to the
instructors there; maybe have one with you as you go over the logs, to
explain things to you. Don't take his explanations at face value, but
get a sense from it and them about how seriously they take things.

Not all squawks indicate a problem with the airplane. Some (many?
most?) may be pilot ignorance. (I've had people squawk inop electric
trim, when the problem was the previous pilot switched it off and the
next pilot didn't even know there was an off switch).

Post questions about the specific FBO here; some pilots may have
experience with them and be willing to share.

In the end, there are some things you'll only learn after you've flown a
plane for a while, and seen what happens.

Jose
--
There are more ways to skin a cat than there are cats.
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