It's a strange notion to some, but the Panda is a reliable Fiat.
As already mentioned, the FIRE engines are pretty built proof and it's been around since the early 80's, only the igntion and fuel management have really changed.
Parts are fairly cheap, servicing yourself is easy (did my last one with gen fiat parts for £42)
There ain't much need of specialists, a local garage isn't going to be scratching their heads over it.
It isn't badly finished and screwed together, perhaps because it's actually built in Poland rather than Italy like the latest ones.
There are very few faults that crop up every now and then, but just looking through the forum should ease your mind, most forums are full of owners looking for help finding faults (just look at the X type Forum). There's very few on here.
Those that do are:
Knocking from rear over bumps - that's a bush in the top mount of the shock worn, hardly a wallet emptier as new shocks are cheap and fitting easy.
Fan modules/motors have been know to burn out - easy and fairly cheap to sort.
After a few years over traffic calming bumps, the front wishbone bushes can wear, this knocks the alignment out a little - as nearly every side road has these, all cars tend to suffer from this.
Batteries take a knocking, I think this is because these cars tend to be a short trip car and that zaps batteries.
There's not many reporting the steering column EPS failures.
Not as many as the Corsa owners, they are pretty awful and I'm suffering with mine in my Combo, the crach pins have collapsed and the torque sensor has a mind of it's own, it's like the steering wheel is connected to the wheels with chewing gum!
It's not something to worry about, even if you do end up fixing one, it's cheaper to use a remanufactured ones from the likes of BBA Reman.
They'll usually warranty it for a lot longer than Fiat.
I'd go for it, there's always a few worries over buying second hand, but they shouldn't put you off.
