Thank you for clarifying that for me.
The Law that relates to property for unmarried couples is the Trust of Land Act.
Even though the property is in your ex's sole name if you have paid the mortgage and have added value to the property through renovation then you will have a beneficial interest in the property.
If your ex renegs on any agreement that is reached then your recourse is to make an application to your local county court for a declaration as your interest in the property. You can also ask the court to consider making an order for sale to realise your interest in the property.
The form you need to do this is a Claim Form part 8 and the court fee is £280.
At your stage if matters can be agreed - perhaps make your ex aware that you will make a claim if he renegs.
If you make your correspondence as a Part 36 offer - then this will mean that you have leverage to seek your legal costs to be paid - if the current offer is less than what a court finally awards you. This is a tactic to get him to pay now rather than mess you around.
Let me know if I can help you further.
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