Capital Gains Tax computation

The asset is mixed use ie business asset and non business asset.

Property aquired November 2002 for £55
spent £25 renovations
Furnished holiday lettings July 03 - Oct 04
Ordinary letting Oct 04 - June 05
Furnished holiday lettings June 05 to date.
Disposal probably November 07 for £135.

I am not sure how to split taper between business and non business ie holiday lets and non holiday lets.

Client clearly has had it as holiday for longer than two years so presume only 25% chargeable.

Am I wrong here?

Thank you to anyone who could help
Jason Brown