From transforming daily commutes to bridging the gap for non-cyclists, e-bikes are the most significant evolution in cycling since the mountain bike—and that’s a win for all.
Build it yourself. Otherwise prepare to spend thousands. Buying a conversion kit and a lithium battery pack is by far the most cost effective option, and it’s not hard to assemble. Swap the wheel from whatever bike you have laying around, attach the battery pack and throttle, done. Takes 20 minutes. ~$500
And personally I’ve found that beach cruisers make the best eBikes. My initial thought was that a mountain bike would be ideal because it has suspension, but in my personal experience I found that even with suspension, a mountain bike is too hard on your back for long trips because you’re constantly hunched over. Beach cruiser is the way to go.