Okay I need help now

I have the typical weekender galley hatch but I also have two 21"x28" doors in back that swing outward. The galley hatch overlaps these doors to make the whole thing water tight. I can't figure out what type of latches to use for this arrangment. By latches, I mean doorknobs, only not doorknobs. I would like to use individual latches for the doors and a seperate latch for the hatch. Does anybody know if this is possible to do and how would I do it/what type of latches.