CGT where bought out ex-partner (not spouse etc.)

[CharleyVN]

I have a number of queries along the same line at present and have sought clarity from HMRC to no avail. I am looking for the correct acquisition cost in the following example:

Mr A purchases a property for £90,000 in joint names with Miss B in the year 2000. Incidental costs of acquisition total £2,000. There is no marriage or civil partnership and no other reason that they would be connected parties for CGT. There is a 75% mortgage on the property which Mr A pays the majority of.

The relationship ends 5 years later and Miss B agrees to accept £5,000 for her share in the property in 2005 as she recognises that she did not contribute as much to the mortgage and the market value of the property has risen to £120,000.

Mr A then lives in the property until 2010 and lets the property until the current day, when he then sells the property for £200,000. Incidental costs of sale are £5,000.

What is the correct treatment for the CGT Computation for Mr A please? I have my thoughts and two separate HMRC advisors have 2 different thoughts, giving 3 opinions in total.

[pawncob]

Purchased for £90k, but how much did Mr A pay? please give purchase details.
Owned as joint tenants or tenants in common?
Any written evidence of ownership split?

[maths]

It seems that you each had a beneficial interest in the property as it seems Miss B sold her interest to Mr A.

If Mr A paid the full purchase cost ie £90,000 and effectively purchased Miss B's interest for £5,000 then for CGT his base cost is £95,000 Ignoring ancillary costs).

Gain would on sale be 200k less 95k ie 105k.

Relief would be available for some part of the gain depending upon how long Mr A lived in the property