OK, here's how to get rid of them.
Get some Permethrin, and get the 36.8% stuff. Probably have to order online as most local shops don't stock the 36.8% and are very expensive.
Also called Tengard Permethrin.
I use to buy it in the 5 qt containers, and now I just get a quart on Amazon for about $25 and last me a year.
I treat the lawn about 3x a year with a 1.6 oz per 1 gal of water solution. Run thu a garden hose with a metering bottle. Hose water is about 2 gal a minute so you can figure out how much to use.
You can spray the boat with a hose or a garden sprayer or even a spray bottle. The goal is to get things real wet with the solution. DO NOT spray metal items like appliances, hardware railings, etc. It will tarnish them, but if you hit some, flush it off with water. But you can spray floors, wood, walls, carpet, drapes furniture, screens, seats, etc. It's somewhat toxic until it dries then non toxic (so hide the cat).
It's the same stuff you make insect proof clothes with and you can make your own, soaking your clothes in a solution and hanging them up to dry... good for about 10 washings. Do not spray on your body. If you must spray your body, us a product containing deet.
For the boat, do a few treatments to "condition" your boat.
It works very well. I've been using it for years in the no see um capital of the world, hot, wet and no wind days.
Now, if you're out on the water, they should be minimal, but get close to land where there's vegetation and standing shallow water, hold on you your hat... they'll carry you off.