Should I buy Office?

Via one of my LJ friends, I got a small consulting gig that involves doing some data analysis on Excel, which I can do on my own time, remotely. (By the way *thank you* to my LJ friend for this gig! Yay paid work!) I could go to the library, but using computers at the library is usually limited to one-hour slots. I could beg and borrow time on other computers, but I am in a different town than usual. Should I just buy Office? It seems like it might be a good investment at this point.