your engine will run much better and quiter if you go back to the stock air box, try
www.car-part.com that is how I found mine, and it was well worth it.
155/80-13" tires are going to be better then the 175/70-13" tires that often get installed, they are also often cheaper.
I would pay that much for a car like that, so I think you got a good deal, I would start with buying a shop manual and going thru the check list of matince, and unless it looks like someone did it, do it.
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