My first couple were crammed into available, unalterable spaces. They were small, but efficient.
The next was 8x10 feet, drop table, dry side and wet side. It was really perfect for its size.
15x9 became available next to the entry to the 8x10. I expanded and attached that area. The enlarger was moved to the new space and I acquired more. There is space for dry mounting and framing.
Caution. Make the walk from enlarger to developer tray as short as possible for the most frequently used enlarger.
Build counters heavy, 2x4 legs and cross/diagonal bracing. 3/4" plywood tops with solid wood edges and beveled.
Build all counters/sinks tall enough so you are not hunched over. Kitchen counter tops are for short women, 5 feet 2. My counters bring the enlarger bases to 38". Perfect for me. My short friends have trouble.
Enlarger bases are usually too small. Either sink below counter height and make a cutout or add framing to extend edges.