There’s sports memorabilia, and then there’s sports memorabilia. My friend, whose ex was a scout for a pro sport, left his memorabilia to his daughter - she sold it for something like $30,000 (granted, a couple big items were the bulk of it). So if you have some idea of what he has, do some noodling around to see what they might be worth. My boyfriend left some signed baseballs - one by Joe DiMaggio - but the sum total would only be worth $2,000 if authenticated.
Check with your attorney, but I believe the value of the furniture would be its resale value - and unless they are valuable antiques, that’s going to be much less than what you paid for them. If you’re not overly attached, suggest splitting the household goods - I doubt he really wants any of it, he’s just using it for leverage. Call his bluff.
Now - if his sports memorabilia isn’t all that valuable, a trade for the furniture might be a good deal. But if you’re thinking of not keeping the house and downsizing, you might not want all that large houseful if furniture anyway.
And agreed - don’t agree to anything, let your lawyer handle negotiations.
