Even though it’s a hefty amount of money to fork over upfront, LaLonde says you’ll likely save money in the long run. If you use public transportation, do the math to see how much you could save over time. If you choose an e-bike over a car, you’re foregoing auto maintenance, gas, insurance, parking fees, and potential tickets, LaLonde adds. “So while there’s sticker shock for a first-time bike buyer, it can still be cost-effective.”
Thanks to clever engineering, the Electric Brompton folds up identically to the non-powered variety. It is heavier than a standard Brompton of course, but quite light by e-bike standards. It has small , suitcase-style additional wheels that come into play once folded up, and the way the weight is balanced means it is quite straightforward to trundle along in that state.  
For many bikes, battery range is more important that total power (because they're all pretty powerful). You want a bike that delivers a range long enough for your rides at the power levels you want. Most e-bikes will have three to five levels of assist kicking in anywhere from 25 percent of you pedal power to 200 percent boost. Consider how fast the battery takes to recharge, especially if you'll be using your bike for long commutes.