Ok purolator is running a promo on oil and air filters and advance auto always has %off so if you use these on your FD this is a great combo deal:

advanceauto site and get 4-pureone oil filters and 1-purolator air filter

thats
4x6.49=25.96
1x16.99
add something else (7.05) to get above $50

go for local pickup
add advance code a123
thats $20 off @50

so your at $30
go to purolator site and download the two coupons
$3 off oil filter upto 4
5 off air filter

thats another -17

so final cost is $13.00