Hardtops seems to be $800-1400 these days, although some people try to get more, which can be worth it if it's the right color and local. I think I paid $750 for mine 12+ years ago with a storage cart and a some minor scratches on the roof. I drove 700 miles to pick it up, but Ocean Blue hardtops are very hard to find. I purchased and installed the spinlocks separately, I think they cost about $60.
It's been on my 986 90% of the time since then, I really prefer the hardtop, but I'm definitely an outlier.