Hi and welcome. Is the bike an S model (with half-fairing and clip-on handlebars) or an N (naked with standard bars)? As it's a 2002 it's a carburettor bike. Fuel-injection was introduced on the post-2003 bikes (which are WAY better looking, of course
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The engines on SVs are pretty much bomb-proof, the only thing that really kills them is running low on oil as a result of neglectful / careless owners. As the bike is now 16 years old, look through the history / paperwork for evidence of regular servicing (the Suzuki schedule is oil change every 3,750 miles, oil filter every third oil change, coolant every 2 years).
But the major thing is, there are lots of SVs out there - don't rush to buy the first one you see. There will always be another one available soon. If you have any doubts about the bike you're looking at, just walk away.
Ask if the dealer is actually selling it directly themselves, or if they are selling it on behalf of someone. If it's the former, the dealer is obliged to fix any faults that emerge in the first 6 months of you owning it. If the latter, you have no comeback at all.
Good luck with it in any case.