I split up from my partner - what are my rights where our property is concerned?

You need to see a Solicitor as it appears everything will not be settled amiciably between yourselves. I feel you are entitled to half and you will be better off doing things legally rather than arging who is entitled to what percentage. Do not pay any money without a Solicitor overseeing the whole operation or you may find you have been ripped off. GET A SOLICITOR NOW.