Electricity bill

I rent in a small 2 unit building for 3 1/2 yrs. Our neighbor is the son and daughter inlaw. They had an electric company come out to see why their electric bill was so high and discover our garage was hooked up to their electric box. shortly after we moved in, my husband had his friend an electrician increase the watts so he can run his air compressor. (note the electrian never swaped the wires). My landlord called and wanted us to call a electrician and swape the wires. We paid our friend to do this. He also mention that we should give some money to our neighbors (his son) since this increased their bill. Our electric bill avgs 45 - 65 a month. Since we swaped the wires, I can't really tell the difference. I agree we should pay something, and offered the $200, she claims that the increase and difference is at 1K. they are going back 16 months, and came up with a figure of $64 a month of an increase, and will me us 1/2 way, and want 32 a month at 16 months.. $544. And this is a amount after "we" had the electrican swape the wires. It was a friend, but we paid him 100 to do it. It would have cost them more. There is no way a air compressor in a garage runs more electrc kWh then our apartment. My husband doesn't run it 24/7. Now they claim our electric bill hasn't gone up, becasue he's never in he garage. He's restoring 1962 VW Bug, if anything it should increase. What are my rights, they are going off their bills.