Right now my goto basic chunk of block storage is WD 8TB Blue drives. Brand new out of the box price per TB is hard to beat in my area, and they’ve been shockingly reliable and performant.
I see the price of NAS drives and frankly don’t see how they could be worth the price is you follow sound backup strategies.
triple your rates. Seriously, a lot of times people don't take you up on it because you're simply not charging enough. I went through a similar thing and doubled my rates and went from struggling to get any bookings to getting more work than I knew what to do with. Do some footwork and figure out what the going rate is for your area and charge the same amount or maybe a little less.