I accidentally bought the wrong cable to go between my IC-756 PRO and the shiny new Heil mic I just bought. Its right on the radio end, but wrong number of XLR pins on the mic end (too many on the cable). The eBay seller accepts returns at the shipping expense of the buyer, but the correct cable costs $25 more than the one I got; I would have been out $31 to fix my mistake. For $13 I got the parts to make the correct connections, savings of $12 over getting the correct cable in the first place, $18 over sending the wrong cable back and ordering the correct one.
Still not sure if I feel smart or dumb, but I do feel lucky.