Z.A.
Super common.
First off: 10% bleach. Now.
Secondly....if it's a structural problem new windows would solve SOME of it. (note the some) It could be many many many of any one, or a combination, structural problems; from as simple as needing new seals to the framing actually being damaged. If you only get drips when it rains...that's your key.
OTW...
If the condensation starts in October and lasts until late May, welcome to one of the dampest places in creation. We actually have more varieties of MOLD in this area then anywhere else in the world save ONE rainforest I can't remember the name of, and it's not the Amazon. Yuck. Most of it's harmless...unless you don't consider sinus issues harmless.
Moving Along...
You don't have what area you live in on your profile, or mention what type of home you have. Areas around here TEND to indicate style & decade built. If it's an apartment, and you look in the fine print on your lease, it's one of those things that SHOULD be covered. If you live in a house, the KIND of house you live in will help determine the problem....but regardless of the type...a vast majority of houses in this area are insufficiently vented. And worse...many DIY'ers have vented into crawlspaces and attics...which then FILL with mold. Sometimes the toxic kind. So put that on your list to check out. Wheee.
The types of houses that do BEST with moisture are those built prior to WWI and are NOT cement-brick-stucco...especially ones that have been retrofitted with kitchen & bathroom vents. Tens of thousands of houses (nearly all of Mountlake Terrace for example), were built on the quick by the military after each of the world wars...and if you're in a cinderblock house you have my condolences. Rented one for two years. Lived in a brick house for 8 years. Brick, cinderblock, & cement all need double wall insulation or you may actually notice your walls "weeping" at night. If you have any of these kinds of houses make sure your furniture is pulled at least an inch away from all walls. And dig french drains as a stopgap measure. Dehumidifiers are a big help as well.
Anyhow...I could go on...if you'd like me to shoot me a message with your home type.
The simplest "fix" however is this: Leave about an inch gap between your blinds and the casing, leave curtains open as much as possible, keep the heat up as high as you can afford (similar to using a hairdryer to clear off the steam from a mirror), & run your fans religiously during cooking & bathing for about an hour.
Good Luck...and welcome to the city. The very very damp city :)