Claiming benefits upon returning to the UK

Hello. I am looking for some solid advice please on behalf of my brother in law who is currently living in Spain. He wants to move back to the UK (he has been in Spain for over 20 years), and is wanting to sell his flat that is now in negative equity. He has become severely depressed, is very lonely, has very little money and also has physical health issues. He currently has a Spanish equivalent of DLA which the Spanish government pay half of, while insisting that the UK should be paying the other half, which they have refused to do so. This however is another matter. My main query is, we need to get him back to the UK before he ends up having a breakdown and is totally incapable of helping himself at all. What help can he claim upon his return in the way of Universal Credit (and help with rent that comes under that), and PIP/DLA? Also if anyone knows how he would stand with getting a council property? He is 58 years old. Sorry for the long post, but it is a very complicated situation and I have only found limited info via google etc. Any helpful advice would be so gratefully received

Thank you for your help Gary. I will have a look at the link you have included.

All the best

Emma