I purchased a boat in Aug 2013 and my then partner

Hi, I purchased a boat in Aug 2013 and my then partner agreed to pay for the renovation and storage of the boat during the project. ( he did not have the money to purchase the boat, so I purchased it instead) We have both been working on the boat over the last 18months. However the relationship has broken down. It has come to light that the receipt from the boat yard was issued in my ex partners name only ( even though I paid for the boat, I have bank statements to prove payment) I have paid for a valuation of the boat and the valuation has come back at £7500 to £9500. However my ex partner believes he owns the boat because the receipt. I have proposed a settlement fee as well as if the boat is sold the first £5,000 is mine and anything above that is split 50/50 between us but so far is refuses my proposal.

Also we purchased a bed and sofa together i march/April 2014 jhe paid, I transferred my half to his account afterwards) the total cost for both items was £2395. I proposed £800 for my half of the items. He refuses to accept this proposal but has also stated I owe him £1,400 for damage on his Jeep grand cherokee. An accident took place 2yrs ago when I was driving the car (Matthew was in the car with me at the time) while reversing out of a car park some damage was sustained to the drivers side rear bumper. No claim was made on the insurance, I was a named driver on the policy however Matthew is trying to make deductions now and asking for the value of the bumper to be fixed. I have not seen any quotations for repairs and fear he is not only making up figures but also using this incident to intimidate me in the situation.

I want to know who legally owns the boat and if he can sell it and then offer me 30% or a percentage of the sale price when I purchased it initially? And what rights do I have to pursue settlement of joint assets I.e boat, sofa and bed ( Bed and sofa are in his possession) Thank you