Just a thought.

If John Smith was selling something, say, a slightly used RSK Mk 1, I would probably pass.

On the other hand, if ironraven were selling the same item, I would give it more than just a passing glance.

Many of the long-time members here have built their reputations by their handles. If they suddenly switch to their actual name for a premium membership, well, suddenly I don't know them from ... John Smith. Unless their handle is somehow tied to their actual name, i.e. John Smith aka ironraven.

Perhaps we could keep the handles but supply the additional information confidentially?

I don't really know what the answer is. Whatever, as I think I said before, someone will be unhappy with the end result. Lurkers with low posts. Newbies with more than enough posts but not enough time registered. Perhaps you could simply revamp the marketplace for now as a yearly fee? Just throwing some more ideas around. FWIW.