I need to get a new built-in electric fan oven. Our current one is
around the standard single oven size, and is plugged in with a normal
13Â*A plug and socket. (It's least 20 years old, probably quite a bit
older, and some years ago a repairman told me parts were no longer
available. Oh, and it just stopped working.)

I am having trouble determining, from the information on
manufacturers' & retailers' websites, which fan ovens require a
dedicated power supply & which ones can be plugged in. I'm willing to
have a special supply run if necessary, but obviously it's a
disadvantage to models that require it. Do they all require that now?

Also, how difficult is it (apart from the electrical supply) to remove
and replace one of these, provided the new one is about the same size
as the old one?