Sounds very difficult.
Renovations take a long time, start to finish. design, planning, tendering, waiting for preferred builders to be ready to commence, build time.
Quite a lot of the house could be out of action during the works. And with limited bedroom space to retreat to, I think it could be a very fractious and stressful time.
Could you fit a caravan (as a bedroom) and/or builder's welfare unit on-site?
Our builders hired a unit from Elliott's like this: www.elliottuk.com/solutions/standard-layouts/office-canteen
It was a tight squeeze for a family kitchen for more than six months, but worked fantastically well - it was delivered by Elliotts to the area at the front of our house (using a crane off the back of a lorry) and we used half as our family kitchen (it had a hot water unit, laminate table, powerpoints which we used for microwave, coffee machine and convection hob, and window and sink). It was very secure. For storing food, cutlery and plates we used the kids' IKEA trofast storage unit (from their playroom which was out of action)
The builder, who we knew well, used the other half for his office. But you could easily use it as a bedroom. Move in a bed or small bunk bed and set of drawers.
Each half of the unit had an electric heater which warmed up the space quickly.
Various layouts and sizes are available from companies like Elliotts.