My sister has been with her boyfriend for 3 years and she is thinking of splitting up as things don't seem to be working out. They have a mortgage in joint names and I was wondering if she left her boyfriend would she be able to sell her part of the property?
She can certainly force the sale if he refuses to agree.
It is going to be very difficult to sell a share in a house to a third party if her boyfriend doesn't want to buy her out - and the mortgage company would have to agree to either option.