That looks fascinating Chalo, and almost exactly what I was thinking for the application. I'm not married to the Coaster Cycles model, that just happens to be the one that Ford GoBike uses around here so I've seen it in action. Which pedicab model have your clients had the best success with?
The application is a tough cookie, but not impossible to solve. We will be transporting lots of relatively small ~30 lbs packages all over the city of San Francisco 14 hours per day, rain or shine. Right now we use vans, which are a poor fit for what we do because of the traffic and scarcity of places to stop. We don't go up the steepest hills very often and we can use vans for those so it needs to be able to tackle moderate hills but not the famous super-steep SF hills.
We have a surplus of Li-Ion 2 kwh 72V, ~40A batteries that are just lying around and can be swapped throughout the day as we deplete them, so that's the easy part. The hard part is that there's just nothing on the market that can carry at least 10 (and preferably more like 20) of our 30 lbs packages, has a throttle, is easy to park or take on and off a center stand dozens of times per day while loaded with hundreds of lbs (which is why I'm interested in a trike or trailer), is durable and dependable, can use the bike lanes to skip the traffic and can make brief stops on the sidewalks for deliveries without people freaking out, but can still use the vehicle lanes and keep up with car traffic on streets where there are no bike lanes. By "keep up", I'm talking about initial acceleration off the line. It's OK if the top speed is below 25 MPH as long as it can get going quickly enough not to tempt drivers to make dangerous passing maneuvers.
We're currently leaning towards an electric motorcycle pulling a trailer for these reasons, but I've been trying to find a solution that can travel in the bike lanes and looks like it belongs there. Most of my co-workers are not bicyclists so they don't understand how much quicker, easier, and less stressful it is to get through a dense city in a bike lane, especially when it comes to stopping to make deliveries. However the crop of e-bike solutions are woefully inadequate, especially as they are designed for European laws where the cities have much better bike infrastructure than SF.