High electric bill for no reason

Is your site metered and billed by the park or by the power company? First, I would check to see if your meter reading is correct. Second, especially if it is read and billed by the power company, check how many days it actually covers (often they are not read on a exact schedule, last month could have been 27 days and this month 35). If it is the power company, often times you get a stepped up rate after a certain amount of usage. Those last few kilowatt hours can be very expensive. Finally, depending upon the cost per kilowatt hour, $260.00 is not out of the realm of possibility. Your rig might have less insulation R value than your neighbor. You might set your thermostat to 70 and they run 75. You might go in and out more often. You might be using electric hot water, they are using gas. Then there is the fact that someone has to have the highest bill in the park. That's just a plain mathematical certainty.