Sylvia,
Garlic and Yeast works, but it takes time for it to build up in the dogs system. Frontline and Advantage works, but they are expensive. You might be able to find a place that sells single applications of it, most places have it in 3 or 4 packs. I would stick with Advantage/tix If you go that route, I heard it's been working much better.
Cedarcide, I personally use and it kills on contact, you will have to comb out the dead fleas. It's not a month long preventative, but a bottle will last you a few months on a yorkie. You don't have to worry about getting it on your hands or breathing it in. I spray, rub it in with my fingers, then comb out the dead fleas. You should also spray any betting with it.
The cedar smell fades pretty fast, you won't smell it the next day.
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