hi there,
it all depends what they want, how many cleans are they loooking for, build clean, reclean, sparkle clean, or are they trying to save money ans reduce the number of visits.
establish what they want, remove floor protection, radiator protection, and what state the kitchens, beedrooms, and windows are in.
then you can make some decisions regarding the pricing.
on a 2 bed house we would expect two people to be able to build clean the best part of two plots per day.
regards
martin