Finally got the robot. The battery's bad, but I've ordered a higher capacity replacement. It should permit nearly four hours of use between charges. I didn't bother to assemble the arms because they're non-functional. Perhaps you can think of some devices to install in their place? A machine that sprays out squirrel feed? A 1 watt laser? A power drill?
Still need money for the solar panels and 4G mifi, but the docking station battery could be the same battery pack I used to power Hampture's air pump so as to save funds. This project might take shape faster than anticipated if I can work out ways to reuse stuff.