I haven't bought the TV yet, I am this close though, I will try
cleaning the power supply, I guess it could be a vent or something. The
owner supposedly brought it to AA Appliances in Boston (they are big,
heard of them before and recommended by NEC) but they were awful. Not
sure if they even thought of cleaning it.

Now, two questions:
- who would be able to perform board-level repairs - someone with
knowledge of electronics, circuits or does it have to be someone with
plasma TV experience. What I'm asking is, is this a matter of finding a
short or something (apologies, as you can tell I am not very
knowlegeable) or do they need to know more about TVs and such

- also, if all the specs are the same (power in and out, amps not sure
what else), would any power board work or does it have to be
specifically for that TV? The TV is fairly old so I am not sure if I
can find a broken one (which would go for probably $300 - $500)?

Thanks everyone for all the replies, it's really helping

Sergiu