Clapton's "Blackie" Strat sold for just under 1 million - ?s I think, not $. I believe that was the record at the time, & it was sold for EC's Crossroads charity in the Caribbean, so that might have boosted the bidding.
The other really expensive one was Peter Green's iconic Les Paul. Green chose to sell it to Gary Moore. You would think that Moore (not exactly a poor man, I assume) would treasure that for the rest of his life, but no, he sold it, then whinged and bitched because the guy he sold it to sold it for more money. What a surprise! As if you have any right to complain when a guitar you sell gets sold again!
I heard a million mentioned as a figure for the resale of the Green LP, but I'd have to look it up to confirm that (if I can find the magazine).