Advantage Multi (for fleas and heartworms):
Online/Mail in rebate: Buy 6 doses, get $30 (w/ heartworm test)
or get $20 (w/o a heartworm test)
Buy 12 doses (for same pet), get $65 (w/ heartworm test)
or get $ 55 (w/o heartworm test)
Heartgard Plus (for heartworms):
Buy 12 doses and get a $15.00 mail-in rebate
Buy 6 doses of Heartgard and 6 doses of Nexgard/Frontline, get a $25 mail-in rebate
Buy 12 doses of Heartgard and 6 doses of Nexgard/Frontline, get a $35 mail-in rebate
Buy 12 doses of Heartgard and 12 doses of Nexgard/Frontline, get a $75 mail-in rebate

Nexgard (for fleas):
Buy 6 doses you get $15 mail in rebate
Buy 12 doses, get $35 mail in rebate