Shocked at your prices of hides, mine mostly cost £5.00 for deer and £15.00 for cow or occassionally nothing from road kills.
Used to use chemicals to help the de-hairing (man-made ones) but having a wood fire and living somewhere where its burning most of the year, I started using ash - if the hide is still warm I wrap it in salt for a few days first.
A week soakin normally does it, sometimes the neck areas can be a pain but most hair comes off without taking too much of the underlaying skin off.
Luckily we are in a windy area and place frames in direct path of it, otherwise the skins would never totally dry. Usin this method, I never had any grease on the hide.