Here's a quick mechanical inspection:
- Take the grill off
- Inspect the cone suspensions for rips,
- Feel the travel of the cone, see how much leeway there is side to side before the coil scrubs against the magnet assembly
- Look very closely for folds/ripples in the cones, they're not as apparent from the front as the back
- Any rips, scrubbing, or ripples = soon to be dead driver
Most importantly if the seller won't let you do that, don't bother arranging to meet. If you're not afraid to replace/recone a driver, price it out in advance.
SVP-CL + IPR 1600 + SWR Goliath III 4x10 = bliss