"Bug-bombing" your yard won't help with your mosquito problem.
Mosquitoes can travel 1/4 of a mile. You need to either remove, treat, or prevent mosquito access to any standing water in that range to prevent 'skeeters from rearing their young.
I use "Mosquito Bits," which are brown crumbles that kill mosquito larvae. You just sprinkle a tiny amount into the water every week or so. My neighbor has a tiny water feature, and since she doesn't like mosquitoes either, I gave her some of the bits to use. A little bit goes a LONG way.
Regarding the fleas, are you certain that they are fleas? What are the symptoms?
I'm asking because chigger season has started here in Nebraska, and the methods of control vary from pest to pest. Chiggers are virtually invisible--one only notices the result--red itchy welts around the ankles or crotch (anywhere that clothing presses against the skin). The itching (and the welts) last about a week.
What animals do you have that can host fleas or chiggers?
We have a cat and a dog, and during the non-winter months we treat those two with "Top Spot" to avoid any issues.
The natural host for the chigger is rabbits. Humans are not a viable host for chiggers because we are allergic to their saliva, and the fact that we scratch the site means that the chigger is scraped off before it can feed enough blood to mature. Any chigger that latches to a human host ends up dying, because it leaves its mouth parts behind in our skin and can never bite again.
Therefore the best control measure for chiggers is to prevent any rabbits from grazing on the property. Insect repellents containing DEET effectively repel chiggers--spray the socks, shoes, and lower pantlegs well.
