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Thank you for your question.
I am a Solicitor and will assist you.
What your partner is proposing is that you hold the property unequally as tenants in common.
If you agreed what he was currently proppsing - then should you seperate - your partner would get the first £55k and half of any share of any left over equity. As you have quite rightly pointed out - you would only get a half share of any equity and if there wasnt any equity then you would end up with nothing.
I note that you have received no evidence of your partner paying the lump sum that he previoulsy said he had. If you are going to agree such an arrangement then you need to see his proof. I would also reccomend that you get a few valuations done on the property now and its current value. if there is less equity that £55k then you need to consider renegoitating the deal that has been offered.
Whilst it is possible to argue that you have contributed towards the mortgage - in the event that the house was sold and there was no equitt - the court would give regard to the agreement that you are now making and the court might uphold your current agreement so you need to make sure that this is a fair deal.
Please note that if you later remarried then the position would change. You would be entitled to make a claim in respect of all of the matrimonial finances - should you divorce - and this would include all equity in the property.
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