Try this idea.
The past few puzzles I’ve worked have gone unfinished because my cat carries off pieces I’m unable to find.
I looked at enclosed puzzle boards, some with drawers, but none looked big enough. Most say they’ll accommodate 1500 pieces, but they’re all smaller than my 48” round table, and I know for a fact, my table is barely large enough to hold 750.
A fitted elastic table cover came to mind and I found this clear polyvinyl one with printed flowers, perfect for coloring with Sharpies. Or for doodling.
A dual purpose solution my cat hates but I love. Win-win.