Kevin, they do supply in singles if thats what you mean?
Ben, Yes I wire and use wax foundation. I normally work out how many frames I'll need for the next inspection and wire them during the week while watching TV and then on Thursday/Friday night I'll embed the foundation.
What are the plastic frames you have? I bought a few a while ago just to test but they had lots of grooves and places for SHB to hide so I stopped using them. They would work out very expensive to few hundred of them also?