Is it worth to get a Bianchi Caurus 909 and rebuild some parts?
From economical standpoint, rebuilding bicycles is almost always unreasonable. For the same amount of money spent on replacement components, it is often possible to buy a new decent bicycle of the same or better level, thus saving workshop time.

If, however, money is not a deciding factor for starting a rebuild, then the answer depends on whether you like spending your time with bike tinkering, and have no other better/enjoyable things to do. If you do enjoy working on your bikes, restoring old things, or want to learn new skills and things, then go for it — wrenching on a bike is often a rewarding experience.