Range from the cheapest replacement of a door frame £150 (Quality Trade Property Service based in SE7) to the dearest replacement of a door frame £300 (Aus builders Ltd based in E14).
Comparing carpenter and joiners estimates for a new door frame gives you an idea of who will be better value but the best way to compare costs is to get actual quotes.
What to do - Get rates and quotes to replace a door frame in Outer London by posting a job with HaMuch and we will send it to carpenter and joiners in Outer London.

"Inside of the door is stained with mould its treated but the stain is still visible. Is it possible to put new sheet of ply ( light oak) to the inside of the door ( 2 doors)"
CANARY WHARF