Buying in to second home.

This is rather complicated so please bear with me.

I currently own a flat, of which I have a £150000 mortgage on the property. I have 1 year left on this mortgage which is fixed rate with Halifax.

I am soon moving in to a new property with my partner in joint name. We will have about a £150000 mortgage on this property. The mortgage is agreed and it is moving ahead.

I initially thought about renting the original property rather than selling. However, I would prefer my mother in law to buy in to the property (by paying off £100k of the existing mortgage). We would then lower the repayments and she would then live in the property on her own. We are prepared to pay any early repayment charges.

The mother in law is in her early 50s and currently does not have a mortgage. She works full time.

A few key questions:

• Can MIL just gift me the money, which I will then use to repay the mortgage allowing her to live in the flat and pay me 'rent'. Should the flat sell, we would divide the proceeds up appropriately. Would a solicitor be prepared to draw up a deed of trust to this affect? Would there be tax implications if I were to sell the home and give her back her money + profit?
• Could I simply put her on the mortgage deed and allow her to pay off some of the mortgage, then move in? Would the bank have a problem with someone of her age being on the mortgage?
• If I were to wait until next year and remortgage, would the bank allow her to be on the mortgage and could I pay off her portion in the meantime? Would there be tax implications?

Thanks a lot,


Rob.

P.S My mortgage adviser, the Halifax and my local branch have all separately suggested the three above options. I am utterly confused and stressed out.