What will be the materials required and how many different features can be included in it? Any software/hardware kits?
The real question is what do you want it to do?
If you want it to strut around doing your laundry and serving you breakfast in bed, then figure on paying several billion dollars to develop it.
If you are OK with it taking two steps and then falling on its face, then a few hundred bucks of junk should allow you to accomplish this.