Help identify bike size

[Ugo51]

Hello,

I'm considering buying a bike. It's listed on eBay not too far away from where I live.
The seller is not very responsive, which is never s good sign. But maybe you can help me.
The bike, a Dawes Audax, is listed as a 53cm frame
But looking at the headtube looks to me a 55cm because from pictures I saw online the 53cm has the top tube and down tube that almost touch at the headtube while this has a good 3-4cm between them.
Of course it's hard to tell from a photo. At least for me.
Does anyone know enough to be able to offer advice?
Thanks you

 

[sjcprojects]

Based on it being like most similar frames, it looks much more like a 53cm than a 55 to me.

 

[LondonClassic]

My first guess on seeing that pic was a 52.

 

[Ugo51]

Thanks!
Very helpful