My wife and I have 2 shitzu's. They recently spent the week with our sons 2 dogs who have fleas. After a trip to the groomer today, we were told they both have fleas. We live in a condo and I have no experience with fleas. I am kinda freaked out now, and feel like I have stuff crawling on me....I don't, that I've seen. The groommer recommended Frontline over K9 Advantage. What do you guys use? We live in a condo in San Diego, dogs are inside everyday except to pee several times a day. I am seeing some pretty expensive prices on Frontline products, is there a coupon or less expensive place to buy this stuff? All prices are times 3 cuz we will need to buy for a 3rd dog that spends alot of time here..our daughters. Any help is appreciated....in advance.