Fairly splitting equity due to one person buying out the other
Five year mortgage taken out in September 2022, so one (and a bit) years left on it. £45k equity according to house valuation. Person 1 is buying person 2 out.
Person 1 put in £40k
Person 2 put in £13k
This includes all furnishings, decor and repairs (which were significant), which person 1 is keeping all of. Person 2 probably paid more of the mortgage, but marginally. Joint tenants, legally.
What is the fairest way to do this/the fairest split? Thanks.