That's probably a wise move.
Though it's too bad you can't hear them.
You could try the EP500 fairly easily. I think this would work.... Take an iPod or other MP3 player and a mini-to-RCA split plug, plug one of the RCA's into the sub's input, plug the sub in, and fire it up. You should get the bass from whatever you're playing. That should at least tell you if the sub functions and the level controls work. Start with iPod volume & EP500 gain all the way down. Adjust appropriately to make sure it rocks.
I don't
think that would hurt the EP500, but perhaps others can chime in.
Speakers are harder to test without an amp, obviously. Your seller has made a bit of a mistake in bubble-wrapping them - it's going to be a hard sell if the buyer can't test them.
But if that sub's good, I'd almost be willing to gamble on the rest if they're cosmetically perfect; cones, finish, posts, etc. Almost. Buying speakers without hearing them is usually asking for trouble. But what's the worst that could be wrong? Blown drivers? Axiom does sell replacements, so you would be able to fix that. Perhaps call Axiom and get some quotes on replacement drivers & crossovers. Get an idea of what you might possibly have to spend to repair them. Then factor that into an offer for the seller.
If it all works perfectly, that's a heck of a lot of system for ~$1,400. An EP500 alone, new, is $1,240. M80's are another $1,300+. And that's not even considering the VP150 or the QS8's.
