Legal/Financial planning advice /check needed

Optimisticpair

Could the clever and knowledgeable check over and advise on any of the following please:

Problem 1

OH2B will be paying the house deposit and I will contribute a lump sum from a divorce settlement. As neither of us wants to get married for a while should we have a legal document to say what we each put in financially if the mortgage goes in just his name?

"Problem 2"

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