I don't care how big a 300zx fan you are... there is no way anyone would recommend someone with a budget of $7K to buy a 300zx.
the 300zx had a price tag over $100K when new.
runs lower than 14 flat in factory form
blah blah..
so it's faster and more powerful than the R32 GTST and 180sx, but $7K is what you have.. so stay away.
out of 180sx and R32, it's a personal choice.
someone mentioned that finding a unmolested version of an R32 is going to be easier than a 180sx.
I only ever spend about that sort of money on cars too.
So I occasionally look around for things in that price range.
and it is more common to see an R32 in OK shape with no major mods than it is to get a 180sx.
all the 180's seem to have some sort of "i'mahomo" bodykit glued on...
just drive a stockish example of both and then go looking for $7K ones..
or $10K ones and lowball them lol