Selling a percenage of our home to our son

Diver

My wife and I jointly own a property valued at approx £380k with a mortgage of £125k. I have some debts I would like to pay off and also reduce my mortgage but we both really love our home and would prefer not to move.

My eldest son (aged 20) is in the army, based in Germany and earning about £23k pa. He is keen to get his foot on the property ladder but wants to stay in his army provided accommodation. He can afford a mortgage of approx £100k

I came up with this idea:
Have the house valued and then sell my son a % based on the £100k investment
Pay off £25k from my mortgage.
Pay off £50k of other debts
Invest £25k into the property

We would have a properly drafted agreement between my son, my wife and myself that would include:
My wife and I would own our % in common
My son would own a specific %
Any party could require the others to use best endeavours to sell the property at the market value within 1 year from notice.
My wife and I would continue to fund the property insurance.
My wife and I would continue to maintain and improve the property except where any such improvements projects would cost more than £5k. Over this amount my son would have the opportunity to invest according to his % or accept a reduction in his % ownership.

It seems to be an arrangement that works for everybody.

Anyone have any experience or thoughts on this.

Please post any replies to the house buying forum. Thanks. Diver

Thanks