Those are good tips moneysense...makes sense to save money too.
We keep the vents closed off in the rooms we don't use, which is only two rooms, a small bathroom that doesn't get used much and the bedroom right next to our inside blower unit.
If we opened the vent in the room closest to the blower, it would freeze in the summer and be too hot in the winter.
During the summer months it would get really hot in our home if we left the blinds open, so now we keep them closed.
One set of blinds started to mess up on us and we ended up buying a new set for our back sliding door.
With the new blinds it stays a lot cooler in our morning room and kitchen during the afternoon when the sun is on that side of the house.