Something to try to save money is to buy the Frontline/Advantage in the largest dog weight possible.
I get the one for dogs 89-132 lbs and can get 3 or 4 doses from one little container/vial for my 22 lb dog so can get a year out of the box.
I had a small syringe that I could suck up 1 cc/ml dose but if you know a diabetic you could get a syringe from them.
Suck it up with the needle on then take off the needle and put the med on the dog.
Saves a bundle!
Each vial contains 4 ml/cc.
For dog 11-22lb use .67 ml/cc
23-44 use 1.34 ml/cc
45-88 use 2.68 ml/cc
89/132 use 4.02 cc or the whole thing.
just round it off.
HTH