A mill isn't about cost, it's about quality of the final beer and the extract you can achieve.
Guy
If you lived here you would have no choice. You cannot buy crushed malt. Unless you import it from the UK.
I keep my saved yeast for up to two years. I cannot remember the last time that I bought any.
Also quite bizarre, crushed and uncrushed are the same price. So really is a tough call, hanging solely on taste of final product.