Selling only residence (abroad) and returning to the UK

[sonoma]

My wife and I are thinking of selling our house here in Latin America and returning home to the UK, I am born and bred English, My wife is Latin American, however she lived in the UK from 1999 to 2007. She has not been in the UK for over a year, she is not a citizen but has a visa (residents Visa) If she were to stay out of the UK for 2 years she would loose that visa and would need to re-apply.
If we were to sell the house would we have to pay tax on the money if we were to bring it to England (This is our sole residence)
If my wife lost her visa would she have to pay tax on the money if she were to bring it too the UK. We would like to sell and return before the 2 years is up to keep the Visa.
Obviously we don't want to pay tax on this money, What are our options. Thank you