I've been around wood heat since I was born.
When I built our home, we installed a wood/coal furnace that's ducted into the central duct system of the home. We heat 100% with wood we purchase from some Amish mills, which I call mill scrap.
They charge 15.00 for a 8' pickup trailer that they load, we use any where from 5-7 pickup trailers a year to heat 4000 sq. ft. We also heat our shop with wood as well, so I pick up 10 loads each year.
We always have 2 years supply of firewood when the heating season starts in the Fall.