If you are exchanging altcoin the answer is simple. Do not trade with people, trade at an exchange. It is a much faster and efficient way of trading as well as eliminating the risk of being scammed.
Have you seen the amount of exchanges that have exit scammed over the past few years? This is faulty logic. otc and p2p trades work just fine when you use your head for something other than to weigh your body down.
Escrow is cheap and/or free here. Over time I have built up some good contacts that I feel completely comfortable trading with.