We did our solar panels first, to help address our home's energy use (our electricity company is a monopoly and keeps charging more year after year). Plus we liked the idea of being green and energy independent, the vehicle is a newer addition to the setup.

Not sure where you are, but even if you can't do solar now, you might be able to do plug-in solar soon! Super popular in some countries already, and coming quickly (hopefully) to the States. And even if you can't do a four wheel passenger EV, e-bikes are a great choice for traveling on the power of the sun.