Back in the mid-80's, I had left teaching and was sort of 'at liberty' while looking for my first computer programming job. To make ends meet, I did some work for a local electrical contractor who wanted an accounts receivable system.
This guy was a crook.
He had a list of fixed-prices services for me to code into the system and one of them was "Cross-linking Electrical Meters". He said that he did this for duplex landlords where they would somehow connect two electrical meters together and reduce the overall bill.
The fact that he was blatent enough to have me put it into his billing system aside, I've always wondered if this is really something that can be done. Mind you, I am just curious. I would NEVER do it.
Another trick he had me put in involved a Yellow Pages Gold coupon (remember those). They required that you present the coupons before receiving the estimate. His non-coupon price was 15% lower than his coupon price. I challenged him on that one and he replied, "I have to pay for the coupons somehow."
I didn't work for him very long.