Last Minute A/C Shopping

We haven't have any kind of air conditioning since we came here and we've been fine with that because we used to live in basement and it's cool (but humid) down there. And when we moved in June, we still didn't feel the needs to install air conditioning since the early part of the summer was unusually cool. However, we definitely felt the heat (and humid again) the last couple days when the temperature went up to 90's and it's always like ten degrees hotter in the house. After multiple nights of sweating like crazy in hell, we all came to a unanimous decision to install air conditioners in our bedrooms so we'd sleep comfortably at nights. At first, we wanted to buy the cheapest one available in the market, which would be the 5,000 BTU and cost ranging from $99-120. But later, we figured out that our rooms were a little bit bigger and would need at least 6,000 to 8,000 BTU. After we did some research, we originally would like to buy it online. But the wait could be too long so we decided to go around the neighborhood and tried to find one in an appliance store. Nonetheless, the hunt was unsuccessful as only one store carried the items but they're old and damaged. Then my father suggested that we went to Home Depot so we checked online and thought that there might be one suitable. However, when we went to the store, the staff told us that air conditioners were already sold out and we might need to wait until the next summer. They also said that we'd buy it online (out of stock when we checked later) or went to another store which might still have a few left (Good: They still had air conditioners when we got to the other store. Bad: They're all over 10,000 BTU orz). Therefore, the first day of A/C shopping was extremely frustrated and fruitless. The next day, my father took me to a store which was located near to his work place. Before we went, we called to make sure they had air conditioners because we're very determined to buy at that point and didn't want to come back empty-handed again. We did buy the A/Cs this time and quickly installed them in our rooms (though the installation was trickier than I thought). When we switched on the machine and felt the breeze, it's literally the coolest thing we've ever done but would there be regrets after we received our electric bills? Who knows?