SDLT Multiple Dwelling Relief for house purchase (main residence) with annexe

Lornsy

Could anyone advise on how straightforward or otherwise it is to file a claim for MDR? We are selling our current home and buying a house which has a self contained annexe. It is part of the same building and definitely less than 1/3 of the total value. It has its own front and rear doors, kitchen and shower room, bedroom and lounge / diner. It can't be accessed from the main house. So as far as my research goes, it qualifies for MDR. I have been quoted £840 for an expert to deal with the application for me. I'm thinking it's a clear cut case and not too keen to spend that if it's just some form filling, which I'd then presumably pass onto my conveyancing solicitor. 
Could anyone advise on whether this is quite easy to do, which form to fill in (I've contacted Land Registry, they helped a bit, but maybe I need to contact HMRC) and would it be on the same form / combined with the SDLT transaction for the main house? I'm thinking yes to this last point but am not sure.
I'd be grateful for any advice.

SDLT_Geek

On the regular land transaction return, that is Form SDLT1, at panel 9 insert code 33.

Lornsy

Great thank you @SDLT_Geek. Definitely doesn't sound like I need to pay someone £840 to do that?! Surely I just ask my solicitor to insert code 33 at panel 9 when they fill in the SDLT form for the transaction (which is the purchase of the house including the annexe).

Lornsy

Hi again,
I also wondered if there are views / expertise out there on how the end of the stamp duty holiday affects things.
We've been told (and my notes / queries in capitals):

From 1 July more of the consideration would be taxed at the rate of 5%.  HOW DOES THIS WORK?

On a price of £699,000 (assuming the 3% surcharge doesn’t apply – you should check whether this has already been confirmed by your conveyancer CHECKED, IT DOESN'T APPLY)

• Completion by 30 June 2021 - SDLT £9,950, or with MDR £6,990
• Completion between 1 July to 30 September – SDLT £22,450, or with MDR £9,950

So does anyone know how the 5% works? And why? And would we just fill in SDLT1 the same way?
Many thanks!

Lornsy

P.S. how long do I have to do this, if it isn't all done at the time of the purchase? Thanks!

Lornsy

Bump...for @SDLT_Geek or anyone else who can help!