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I cannot profess to being an expert in IDing Vodder, but it looks good to me. The money sounds fair too. Really in all cases you have to use your judgement about the quality and the 'feel' of any piece all over. I expect that even if you are new to this (me too, but everyone has something to learn) you can tell great quality construction and materials from lesser so. For the money though I'd say it was worth it anyway.
Hope a Vodder-phile will help you out here.

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condition?
I don't know if this is a big concern, but to me it seems that at least one (middle) of the drawer handles is broken. Also, in the top photo it looks like the desk top is warped.
I am definately not an expert, but I don't think repairing the handle would be easy to do. I would make sure you can live with any "issues" before you buy.
Just my two cents.

Check this link out. Looks...
Check this link out. Looks like a vodder desk made by H. Sigh & Søns Møbelfabrik.
http://www.deconet.com/decopedia/object/11328/Writing_desk_by_Arne_Vodder
It looks like the legs taper a bit more on your desk, but overall looks to be the same. The drawer compartment should move so it can be placed on either the left or right side.
The lock could be a later addition.
Hope this helps!

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That is definitely not an...
That is definitely not an Arne Vodder Desk.
There a few variations of this desk made by Vodder and they all usually have same brass hardware/bolts/nuts that hold the legs together on the upper outside part of the legs.
This desk appears NOT to have those visible. In addition to that the leg shapes are very different.

Thanks spacepirate1 I did...
Thanks spacepirate1 I did not notice the lack of the brass hardware on the legs!!
Good eye!

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