
I have frontline spray too - as it can be used on my cat & dog both. I don't see the need for monthly treatments at all.
My home is also treated with a home treatment such as Acclaim (£13.47 in Boots chemist) which prevents fleas breeding - THAT is the key to flea control as they don't breed on the animal, they hop off and take over your soft furnishings. Other similar sprays are Indorex or Skoosh (but the latter has not had much positive review).
Worms were less frequent til I moved to a more rural area, now it's every 3 months strictly. I found an online site which does a special package for a year's worth of wormers (Cestem, which is a new type but as good as any other) and ordered them on New Year's Day! But will worm more frequently if I see evidence of infestation (as I would with fleas). I also worm & deflea my cat every time I do my dog/s - you have to as they can re-infect each other.
I don't breed dogs or cats, but have had cats for over 25 years and lived with dogs a great portion of my life - and the regime I have now I own both, works.