Siding work needed- what should I do?

[Sam Zawatsky]

Hello, 

I'm slowly fixing up a  rental property in Tallahassee, and it is about 1300 sq ft. Part of it is brick, while the rest is sided with what I believe is T111 siding. The T111 areas are rotten at the bottoms now and actually there is a piece high up on the side of the house that seems to have gotten warped and is letting a bit of light into the attic that I have seen. What is the best thing to do in this situation? How much should siding replacement cost?