I've never had as much luck with wallets as with purses. The leather is much thinner and the scratches don't fade away as much. I don't think dunking would be helpful since the leather won't really plump up and there could be some glue inside that would loosen if dunked, but there do appear to be some water stains so you may need to saturate the exterior. The interior looks pretty good. I think I would start with vinegar. I don't think that black mark will go away.Hello - hoping to give this as a gift. I have rehabbed several bags before, but never a wallet. Am wondering if anyone can recommend the best way to clean this - I prefer dunking because it does a more thorough cleaning, but with how there are several layers of leather with a wallet, I wonder how well it would work. Also if you know anything about this, would love to know more.