we'd all love to only do the "better" stufff" and not have to deal with insects, cockroaches,wasps etc, but you really need to cover all pests, rather than a select few, also I know using BOP's can be good in city areas, train depots etc, to scare off roosting birds, I cant see the same happening on farmers fields, and the hours spent in exchange of catch/kill rate, I would imagine to be very long hours, but low kill, cant see a farmer being happy with that, not when he's paying out money
to start with your mate could simple work out what he needs to earn weekly, to pay the bills, then div