This morning we had the city inspector out to check the water heater. All is well, and he didn't have to go through my messy house after all. CO alarms are plugged in upstairs and down. They're supposed to last ten years and then let us know when they need to be replaced. They also set off the alarm when they get unplugged to help prevent kids from unplugging them and parents not knowing. Now we will have them for the new house (one less thing to buy later).
We set up the new dehumidifier downstairs last night. It's made a big difference! Again, a good investment we can use in the new house.