sigma 50-500

Just seen a mint sigma50-500 f4-6.3 apo dg go for £460 mrs out so didnt have the bottle to bid

I sold mine on here a few weeks back for not much more than that.

Do these come up often, my brother will be after bigger zoom in a month or so . He has my old gx20 which i could not get to autofocus with hsm lenses could not work out why ?

No they don't come up that often, people tend to keep them as you really won't get better IQ or range for £500.

No reason why a GX20 shouldn't autofocus with a HSM lens, the K10D/GX10 needed a firmware update but later models were fine.