The land’s registry is on the name of my father, whereas the construction cost of house was paid by …

The land’s registry is on the name of my father, whereas the construction cost of house was paid by me n the expenditure ratio was 1:1 on the overall property value. Since there are more legal hires therefore what to do to ensure that hire ship to be exercise on my father’s part only in future. “I am not sure whether a hand written statement of my father will be honored by court/law at time of the distribution of inheritance (house).”