Additional Dwelling Supplement Queries

[glyall]

Hello,

I currently own a flat in Dundee. I am looking to move to Edinburgh to be with my girlfriend. She owns a flat 50-50 in Edinburgh with her friend. We intend to buy a cheap flat in Edinburgh together which needs renovation and live in it together as both of our main residences. We realise we'd have to pay the 3% Additional Dwelling Supplement for this flat. In 6-12 months, we intend to sell this flat (to ensure we can actually live together ok!) and buy a house together. Since we would be replacing our "main residence" (the Edinburgh flat) with the house, I'm guessing we wouldn't have to pay the Additional Dwelling Supplement again, since we already paid it for the flat and we'd be replacing our main residence with a new main residence? Do you have to live in a flat for a set amount of time before it is classed as your main residence? Is 6 months enough?

I also have another question with regards to main residence, my girlfriend can't convert her current flat into a "Consent to Let", since her friend who owns half the flat will still be living there. Will this effect what is classed as a main residence, as essentially she will have two homes?

It's all very complicated!