When tbh's are constructed, it's good to make them sturdy. I have found that carpenter's wood glue works well to give additional holding power, but the main assembly item is 2 inch dry-wall screws that can be driven with an electric drill and a Phillips screwdriver bit. Run a bead of glue along the wood, then drive several of the screws in quickly. Assembly takes little time.
My hives are painted with whatever is available. I find discarded paint occasionally, but many paint stores have gallons of rejected paint mixes that they sell for a few dollars. The varied colors of hives that result perhaps reduce drifting of honeybees between hives.