We had ours done inside and out when we put it on the market. It's a 4 bed detached with 2 lots of french doors at the back. I just found a local window cleaner and asked if he'd do it because I really couldn't face doing them myself! Cost me £25.
Normally I do all this sort of thing myself but I really can't be arsed- especially as we're effectively moving ourselves, in 2 weeks time. It IS only 250 metres and we have hired a lift back truck but none the less: what we 'save' on removals I will make up for by hiring people to do the jobs I a) don't want to to do and b) haven't got time to do!