Jack, you will find that ,in Scotland, a holder of a tenancy CAN charge MORE than his/her original rent to a subtenant. There is NO maximum amount, as long as the Council/ landlord agree that it is not an excessive amount. For example,the increase may be necessary to pay for extra furniture or insurance . There is, however, an ABSOLUTE maximum time period of subletting, of 12 months, (6 months originally, then increased after consultation to 12), I was somewhat surprised to read that this is the case, but, that is my home country for you , rightly or wrongly !! A good point well raised, my friend.