Excellent price, this would be the best I've done, ever.
Walgreens.com right now has their regular buy-2-get-1-free promotion on hair care products, including Rogaine. Regular price for the 3-pack is $53.99. They also always have their welcome code for new accounts, 15WELCOME, for 15% off the first purchase with a new account.
And there is also the $10 coupon if you purchase with VISA Checkout (I think this exists at all times, but this coupon is one use per account, so if you have used it previously you won't see the opportunity to add it).
And as usual, Rogaine.com has a $25 rebate if you purchase two Rogaine products at the same time.
2x$53.99 (for 3 boxes) = $107.98
15WELCOME 15% = -$16.20
VISA Checkout = -$10.00
$81.78 before tax.
After rebate that is $56.78 for 9 bottles, or $6.31 per bottle.
When paying, put in the 15WELCOME promo code and then select VISA Checkout as payment. After Walgreens.com picks up the account information, the $10 coupon will be applied at the next screen with no extra input.
(it will also work on the topical solution, as it has the B2G1 promo as well).
Side note: I have successfully done a Rogaine rebate via a purchase with Walgreens.com but it was f'in painful because I submitted a screenshot of the invoice. It took me 4 months and many phone calls to get it done.
I think this time I will either submit a scan of the invoice they send with the package, or print out the invoice from the internet and scan it. I will not be doing a screenshot of the invoice again - too painful.
See Wiki for info on rebate. Must sign up for their rewards program to file rebate.