Re: Theme compatiple with Multivendor Marketplace, Advanced Report...
It's unlikely you're going to find a theme that's compatible with all extensions, much less advertise compatibility.
I would recommend focussing on finding a high quality theme from a trusted developer (look for positive reviews on marketplace.magento.com).
Good extensions should be relatively compatible with any good theme. Some of the extensions that you mention are unlikely to be very theme dependence, i.e. advanced report is an admin feature, one step checkout handles most of its styling itself, cash on delivery is a built-in payment method that doesn't require any support, affiliate is likely to not need much in the way of styling.
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My suggestion, instead of searching for themes which are compatible with Marketplace, one-page checkout etc. you can look out for modules which are compatible with all themes. There are many e-commerce plugin development companies which develops many plugins which are compatible with most of the themes. If you want to know more about multiple themes compatible module contact us.
One page checkout with 1500+ Downloads, Multi-Vendor Marketplace with 1000+ downloads only at www.Knowband.com, Contact us: email@example.com.