Thank you for your email. The pilots and flight attendant were excellent. The plane either did not have power or its APU was down and they were unable to cool off the plane prior to boarding. The pilots let us know before boarding and apologized. They started the plane quickly and it cooled off. They handled it great. Minor inconvenience and not a big deal but wanted to mention that. Shortly after takeoff I noticed the flight attendant open the luggage compartment door, make an observation, then notify the pilots. I noticed when she opened the door it sounded louder than normal. The captain came back and looked in there as well and I heard him clearly tell her “the door is trying to seal, but the seal isn’t quite good enough.” I don’t remember his exact words following but he said something along the lines of that it would be okay and they would monitor it. We had no issues and it didn’t appear to cause any problems. It was not loud in the cabin and everything was comfortable during the flight. I would like to know whether or not this is a potential safety concern going forward. Especially since we are scheduled to fly home on the same plane.