I was watching a super 7 long bed on ebay today and the last bid was over 5k au although it did look in immaculate cond – for 5k i could buy a chinese lathe that would eat the super 7 !
There are many more things to factor in with a lathe purchase , will it fit where you want to put it ? Does it need 3ph power ? Can you get the machine to where it will live without killing yourself or disantling it to the last nut and bolt and carrying it in piece by peice ?
Will it do what you want ? If you play with cars or bikes on the side you may need a larger spindle bore , longer bed or more swing over the bed / saddle .
Once you have checked over the specs on a few brands of lathes to see what will meet your needs you can then cull the ones that don't make the grade . After that you should go and look at some examples in your price range – both new and used with no intention to buy as you are just gathering info and sometimes once you look at something in the flesh you may not like it – i have seen some photos touched up or taken at certain angles so not to show bed damage !
My usual advice is simple :
Don't buy brand "A" or "B" just because of a name or some bloke at your local club likes this brand , you need to look at your needs and look for a make that has those specs be it myford , boxford , harison or chinese / taiwanese.
If you know nothing about how to check a machine for wear and its not just the bed the ,leadscrew ,headstock bearings , tailstock barrel , cross and compound slide feed screws all come into play ( excuse the pun !) you are better of buying new provided you can buy a machine that meets your needs .
It really is a bit like hopper said in regards to cars – those that know not how to fix or rebuild usually buy new as they want to get in and drive it not fix it and the tinkerers / enthusiast buy used as the like to play with them .
Ian.