Tourist Visa Funds

Hi

My brother is going to be applying for a tourist Visa to visit me for about 10 days. I was wondering how much money and how many months' bank statements does he need to show.

Also is it worth me writing a letter that I will bre supporting his expenses fully while he is here which is actually true. He will be staying in my rented two bedroom flat where me and my Mrs stay. If yes then what does he need from me documents wise?

Thanks

Also he does own two properties back home, maybe its worth showing evidence of this too?