I went from a brand new townhouse with gas forced air heat to a 37 year
old single family home with the original oil burner. The new place is
3x the size of the old one and it's the same price to heat/cool.

The townhouse was built so poorly that I could feel the wind blow
through it. The 37 year old house was built better, but has had all
the windows and doors replaced with modern units which probably helps a
lot.

-rev