I use both of those too. As long as you have the prescription for the Iverhart Plus, you can go online to find a deal. Frontline can be purchased at pet stores...I got mine really cheap at Sam's Club(wholesale kinda store).
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD