+12 OHE bonus greathelm

[Crooksncastles]

only bonus on the helm

[Fesok]

Just to be 100% clear, it is bonus and not ranks, right? I'd pay 10M for sure, and maybe as high as 15M. I don't know if the market as a whole would value it higher or lower than me, that's just what I'd be willing to pay. If you haven't already you could search for OHE bonus items to see what they've sold for in the past.

[Maerit]

Is +12 to ranks even possible without Spire services?

[Roblar]

Is +12 to ranks even possible without Spire services?

No

https://gswiki.play.net/Enhancive_item_level_requirements