Stamp duty on shared ownership

[Medievalist]

Obviously we will take legal advice but we're just starting to think through the practicalities of buying a house with MIL.

The plan is that MIL sells her house as she needs to move somewhere more accessible and practical and not live in her own. We do not want to sell our home (which is mortgage-free) but are willing to take out a mortgage to buy the sort of property that would fit the bill and live in it with her.

Obviously for MIL this would continue to be her only home. However, for us it would be in part a second home. We don't want to sell our existing home for a variety of reasons, not least because we have adult dcs living in it.

Now we've found somewhere to buy and MIL has had an offer on her home, we're trying to do some sums.

If, for example, MIL's contribution covered 1/2 the cost of the property and was her only home, and we took out a mortgage for the other half which would effectively be our second home, does anyone know how stamp duty would be applied?

Disregarding the stamp duty for a moment, do you have a mortgage company lined up who would agree to this without your MIL being on the mortgage? Because they will want a charge on the house. Also Capital Gains Tax - I'd check the position on that - and, after a few threads on this very issue on MN, if you have any siblings what happens when your MIL dies and the estate needs to be distributed?

I think you'd be best to take legal advice on the SD as second homes incur a higher rate.

We've had quotes from 2 mortgage companies but are awaiting more detailed advice from a mortgage broker.

MIL's name could be on the mortgage if necessary, though as she is contributing the proceeds of her house sale and we are meeting the cost of the mortgage I didn't think this was necessary.

DH doesn't have any siblings and FIL died a few years ago.