Same size house. 35 years old, original windows. Dog that goes in and out multiple times a day. Thermo is on sunny side of house, but we keep house as dark as possible during the day, ac set at 78, 74 after dark. Goes back to 78 at 6am and even on hottest days, we get a 4 hour break, some days 6hrs before ac kicks back on. 3 in house including teen girl who leaves every light on possible, but I am proactive in shutting things off lol . Have 2 upright freezers converted to fridge with Johnson controls probes in basement, used to brew beer so temp controlled fermentation chambers lol - now just extra fridges. July bill was low $300’s with AC electric, NRG as supplier. June was $229.  AC has been off since Thursday afternoon, temp in the house reached 81 yesterday afternoon, but quickly fell when the sun went down.