i like the idea bcuz I can buy a cheap merc and train him then sell him for 2 more shitty mercs then train them then sell them for a super muttie. Saves me caps but takes alot of time. Atleast I get to train my char and mercs at the same time.
And if I want to sell my mercs to a player then why not? If i want to buy a merc from a player why not? You cant expect us to do the "ok give me money first then you get merc. No you give me merc then I give money" crap do you ? You remember fallout 1? When you can buy tandi from Garl ? She shows up as an item that says "Tandi" with her face. Why not do this with mercs and slaves?
Kinda like Charon and the contract thing, but I don't think we need to change the way we trade slaves (and if mercs) since there is no recorded scam concerning this which as I'm sure has been a complete utter fucking shock to the community.

But besides it being profitable this will give players a chance to get mercs by trading a resource like.... 10mms, (good commodity considering they're a tad rare in ncr) or even HQ materials, etc... trade a BA for a Supermutant, you get the drill. I'm sure leaders are really hating the caps only for mercs...