Value of a Columbia Model AU Phonograph

[Calle]

Over here in Europe American phonographs (or gramophones as we say) are not very common.
Recently I was offered a Columbia Model AU and was wondering how much it may cost...
As I couldn't find many information on internet and as the seller wants me to give him an amount which I want to pay for it...?
Can anybody tell me ?
Btw: are there some things I need to pay attention to (weak points) ?
Thanks !

[Edisone]

I can speak only from experience: I paid $450 for the Standard Talking Machine version of the AU (only difference: the ½" spindle) about 12 years ago. Both the crank and elbow are reproductions. I would not pay more than $550 for a Columbia AU, even if in pristine showroom shape, mainly because they're really only good for display - I like to USE my machines.

[gramophoneshane]

There's one listed on this auction site with an estimated value of 700 euro.

http://www.liveauctioneers.com/catalog/23050/page8

[MicaMonster]

Before we jump too far into a purchase, I must......MUST advise you to test the machine thoroughly. The AU has many soft brass gears, and a notoriously difficult to adjust governor gear (which also.....wears unevenly with age). I have sold machines that run like Swiss watches for $750. And machines that run "OK" for $350. They always need a new spring installed, for some reason, and spring replacement on these is a careful job because of the way the mechanism is assembled. Make sure it can play through ONE 10" 78rpm disc before considering purchase.

-W