I like to think of blank pages as mini whiteboards. With a multifunction copier i can print out lined, grid paper or specialty layouts and whip it through the scanner once im done with it keeping a digital copy. 3USD buys me 500 pages, and with a laser printer [250USD], toner refill kit, etc. that comes out to less than a cent a page, or 3 cents if I amortize the printer over 10k pages (assuming it breaks once it hits its one month maximum duty cycle, which is stupid conservative).

That plus a nice fountain pen [Lamy Safari 18.7USD], ink [J. Herbin Perle Noir 7.2USD/30ml], mechanical pencil [Lamy Safari 12USD], pencil leads [Uni Nano Dia 0.9USD/20leads], technical pen [Rotring Isograph 16.3USD], and I've got a nice little setup.