I'm the owner of a 3-story commercial building in New York City. I basically have 2 tenants: One using the ground floor and basement, the other using the 2nd and 3rd floors. I am trying to sub-meter the electrical use of each tenant so they can pay for their own usage (and have an incentive to conserve). For the last several months I have been interviewing licensed electricians. Apparently, though there are two separate fuse boxes (It's an old building.) they each have both upstairs and downstairs circuits mixed up in them. This, I have been told, will make sub-metering a more complicated and expensive job than it should be (potentially over 5 figures.) as it will involve rewiring. Now, in my experience, most licensed electricians think Arduino is a kind of pasta. They are not hackers, not creative, and never look for unconventional solutions to solving problems. (I'm not knocking the guys, but this is what joining the rat race for survival does to people--especially in NYC.) It never even occurred to me that there might be an unconventional solution to my problem until I spotted this 'ible. If you: Have the skills to implement an adaption of this set-up, or have a proposal of your own as to how to solve my problem; are close to New York; and would be willing to consult with a licensed electrician and myself, you may very well be able to save me $5k or $6k, 60% of which would go to you if the plan was adopted and worked. (Otherwise I'd still compensate you for your time at a rate we both agree in advance to be fair.) Anyone interested please PM me. Thanks. PS I don't think of myself as a businessman or landlord. I inherited the building, would sell it in a heartbeat if my brother (who I co-own it with) let me, and I'd rather be writing and making stuff out things I find dumpster-diving than collecting rent checks. But since I'm currently stuck in the role, I'm trying to make the building as green as I can.