Double room, study, utility, balcony

I am a single Mum of a 14 year old boy and an 18 year old girl. We have top floor that we only use occasionally for guests, and on that floor we have an en-suite double bedroom with king size bed (brand new mattress), fitted wardrobes and private balcony, plus your own study and utility room. The house is on the market to be sold so I cannot guarantee a timeframe but would say min 3 months, max 12 months. Our flatmate needs to be very clean and tidy because there will be viewings and their room will need to be available to be shown.