Thanks for your question - I am Sam and I am one of the Uk tax experts.
I would need to know the actual dates this was her main residence (the time she physically lived there) as this will then form the consideration of any private residence relief due.
Did she conduct all aspects of her life from this London flat (so registered address with HMRC, National Insurance office, bank, dentists, electroral roll, doctors etc - and was council tax paid by your sister throughout the period of ownership?
Did she spenfd any time at the other property - or was let out throughout the period of ownership of this new property (so from April 2011 to 9th Nov 2012)
I also would need the dates that the flat was let out - and clarification that this rental income was declared to HMRC as although your provide total number of days - I need to see how this forms a pattern.
I also need to know about the £75000 paid to the project manager as this seems a large figure for a refurb - perhaps you could also advsie the purchase price, the actual work undertaken and the selling price.
I also have a concern that as this property was sold back in Nov 2012 - has this capital gain ecen been declared to HMRC? Or are they asking after the sale of this property under enquiry?
I can then formally advise the relevant reliefs due (if any)