A lot of good options for buying online. A mill, some storage space and some freezer space will make buying online a lot easier and probably cheaper (which may help your wife accept the lost storage space).
A mill is not essential if you buy your grain online but IMO it's a good investment if you end up trying different shops that may have their mills set differently. A good two roller mill can be picked up new for under $150 but if you look around local homebrew groups or craigslist I bet you can find one used in the Seattle area for under $100. The corona style mills are a little cheaper but a well made one these days runs the same or more than you'll find a used two roller mill. I have both and wish I had just bit the bullet and bought a roller mill from the start. Way more consistent crush and better lautering.
If you tend to use one or two base malts for most of your recipes, consider buying those by the sack if you can. That will often significantly reduce the cost of grain. Places like MoreBeer sell in 10lb increments which is also cheaper than per pound. If you're brewing every two weeks, you're probably going through a fair amount of grain unless you brew small batches.
If you have some freezer space, consider buying hops in bulk as well. A pound of hops is usually the same price as buying a few ounces individually. Lots of great options out there for bulk hop purchases and that can save a ton of money, especially if you brew a lot of IPAs.
Buying what makes sense in bulk will also help reduce your shipping costs over time versus buying a recipe or two at a time and paying shipping every month.