Franchise set up

we have a client running a succesful cleaning business (domestic and commercial). he is set up as a sole trader currently

he is interested in franchising out his business as a vehcile to growth and has already got some ideas on the income etc he can acheive

we're looking for some advice on the best way to set this up for him e.g. new co for the franchising alongside exisitng set up or roll into one?

as a side issue, any problems in splitting the domestic and commercial business into two co's?

any comments from AW members with experience in this area greatly appreciated