Keep your eyes open on deals.
I'm lucky I work in a somewhat rural area where most have their own trees and the price of lumber is bearable. 4/4 to 6/4 runs as follows:
hard maple $1 to $1.50 bf
cherry, walnut $2 to $4 bf
oak, ash $1 to $2 bf
Qualitywise I use about 70 to 80% and then tinker with the scrap for things such as cutting boards and such, the greedy type that I am