There is a lot of work and materials to make one. Whether you use wire or oak slats. Around here we use 2 compartments with net funnels that let the lobster in and directs them to a bag of hanging bait. They take a small piece and move into the 'parlor' and the nets keep them from easily getting out. Its highly regulated and escape vents and numbers are required on each pot along with pot warp and a marked bouy. In Belize
they make an oak slat rectangular box and use funnels made from the slats. No netting. They also put the traps in areas without the marker bouys. They spot them in the clear water
from the surface or use a pvc tube with a plexiglass cover. Thats because of the high theft rate.
Its really a lot of work and other than diving
for them, if you like the adventure, its cheaper to just buy them.