How to value a site's worth by earnings?
 

Is there a difference between sites that makes their revenue mostly from rebills and sites that makes their revenue from ads? How it is commonly calculated nowadays?

6-12 months for average sites.

ads or rebills would make difference if it's about really big money on monthly basis.

At the end it all depends on the traffic that site has. Is it targeted or not

Generally sites which make their revenue by rebills are paid sites (membership is required to view the full content and peoples must pay a monthly fee to see the content ) and the others which make their revenue by ads are free sites(no membership required).

See my signature for a program with paid sites, and for free sites you can think of youtube, google for instance or news websites and others.

How about NOT memberships and their rebills BUT VOD or tangible goods ( like DVDs) :thumbsup