If he's off to work then I'd charge him a "cleaning fee" when he returns but that's me. How you raise your offspring is up to you.
Now to your questions,
I'll bet a thermometer for the fridge would cost less than the chocolate milk and a lot less stressful. I don't know of anyone that recharge them, just replace.
A smell of dust burning the first time the furnace is run for the season is normal, so what you are smelling is subjective, have you used the furnace in the past?
2012 Laredo 303 TG
2010 F250 LT Super Cab, long bed, 4X4, 6.4 Turbo Diesel