Replacing a back boiler?

Hi, we have a 30yr old back boiler which needs to come out.
Is it possible to just replace (and relocate) the boiler to a combi? Some rads need uprating to doubles but we are unsure of their 'new' locations as further works (maybe structural) are pending.

My thoughts were to:
(1) replace the boiler with a combi
(2) have the rads flushed and;
(3) fit a Magnaclean at the same time

Is that a sensible approach?
An idea on cost would be helpful too!

Many thanks in advance.



Additional info:
Our house is a 3 bed semi, and I was thinking an Ideal Logic + Plus HE30 would be sufficient

Bill
November 2012