Just go here: https://ondemand.gillette.com/starttoday
Under $2/blade for the Turbo makes me happy. And yes, I know other companies have cheaper blades, but be sure to tell me that in the comments.
Basics: do a subscription, $3 off 1st order, 4th order free.
Normal price for Turbo: $13 for 5
Normal price for Proshield: $21.45 for 4
Turbo 4 orders (20 blades) = $10 + $13 + $13 = $36 or $1.80/blade ($3 off first order, 4th order free)
Proshild 4 orders (16 blades) = $18.45 + $21.45 + $21.45 = $61.35 or $3.83/blade
First order comes with a free handle.
Oh, and free shipping, no commitment or contract, cancel anytime.