I was thinking of selling this fully refurbished HLV-H lathe (1960's I think) with Sony DRO.

It was an old friends home workshop pride and joy but no longer needed.
It has been recently fully refurbished by ZMT in the UK who are well known Hardinge dealers.

I also have a range of accessories inc fixed and travelling steadies, ball turning attachment and 3 + 4 jaw chucks.

It is based in UK but does anyone have any recommendations as to sale value I should ask for ?

An, HLV-H in pristine condition goes for around 15-20k USD on ebay. However, I was at an auction a couple of months ago and a "used but nice" one sold for 6.5k. I'd consider that a steal. Just the ball turner is 1200-1500 on ebay. I'd say a restored HLV-H at 12k would be a good deal...15k would be reasonable. If you've never used one before you will never want to run another lathe. It's worth it just for the threading. I'll bet you can single point 5 times faster than with a "threading dial" lathe.

A 1960's HLV-H sold on ebay for £3100 with ~£1k worth of copy attachment but without DRO.

I would guess a radius turning attachment in the UK has to be worth at least another thousand (if sold separately) and the DRO, ?, a few hundred.

The ZMT refurb must also have a reasonable value. Why not ask them? (They are very helpful and easy going. Ring them, as they don't have email in the shop apparently)

If you have any use for the lathe, it'll be worth more (to you) than you get for it. So, don't sell it unless you have to :)

its worth about 12,000 usd

The Hardinge radius attachment is nice...but VERY limited. 99% of the time we use a corner radius mill mounted in a toolpost collet to generate a radius.

I see that machine in the US running in the $8k-15kUSD range