Latex Foam Mattresses

I have been thinking that we may need a new mattress latex in our master bedroom. The mattress and box spring that we currently have in there are sagging in the middle. My hubby says that the problem is not the mattress but the box spring and the bed frame that it is mounted on. My hubby wants a queen size bed that has drawers fitted into the base but we haven’t been able to find one. He says that if we can’t find one soon he will build one himself.