mid-15c., apparently from Old French barater "to barter, cheat, deceive, haggle" (also, "to have sexual intercourse"), 12c., of uncertain origin, perhaps from a Celtic language (cf. Irish brath "treachery"). Connection between "trading" and "cheating" exists in several languages. Related: Bartered; bartering. The noun is first recorded 1590s, from the verb.
Inevitably some people may feel like they were taken advantage of. One way to diminish inequities is to engage in dollar-for-dollar trades. For example, if you would like to trade your housecleaning service for someone’s couch, try to break down the goods and services to the dollar amount. If the two of you decide that the value of the couch is worth $200, why don’t you supply a gift certificate for $200 worth of housecleaning services? It’s a wise course and ensures all parties know what they are getting and what they are offering.