Hi, welcome to the site. My name is Max and I will help you with your question.
This is possible to do, although as you can imagine, it's not normal to do it and you might find that most commercial high-street lenders are unwilling to do this. Usually, they will only lend where they can secure their lending using a legal mortgage, which requires all those people on the legal title to agree to the mortgage.
What you could do, though, is perhaps agree between you that the property be transferred into your sole name and that you borrow accordingly. You would need to get a lawyer to draw up a deed between you which confirms who owns what in the property, but this is one way in which a commercial lender might be more willing to lend to you.
The first port of call for you would be a good mortgage broker, who understands which lenders are likely to agree to something more outside of the box.
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