Could you live off the land

OK, are you one story or two?  I'm asking because you can go down now and buy window boxes, like you'd do as flower boxes, get the brackets, etc. that you'd need and literally turn every window of your home that's in any way in the sun a growing medium.  Buy seed now that would work for both the window box ideas, any flower pots that you can use on the back or front porches.  Thinking in terms of limited sun space, if you find an area even five feet wide, consider vertical runners for things like peas.  Re-evaluate your yard completely - if you have any flower beds, consider ITSHTF that you'll pull them up completely and they'll become full time vegetable gardens.  If you're worried about stealing, blend in things like carrots and other underground growers as they're hard for people to notice what they are. Potatoes.  You can think of ways to "hide" what you're doing and feel a certain amount of pleasure in knowing you're doing it right under their noses.  But some of that will take some mental legwork now so that if you need certain things they'll be in place or so you can take your time in finding them and thus look for the best bargain.

 And think "outside the box" in terms of pots for your vegetables, you can use things like rubbermaid containers (the big ones) to use your back deck as another garden area.  Use a drill to put some holes in the bottom for drainage, some rock in the very bottom to help with drainage too and then dirt, you can convert your back porch into a decent size garden, outlining the outside of your deck so that your still able to use it for recreation for the kids but it'll be a garden area too.  You can go vertical here too, using the same idea as different level potted basil and parsley gardens that are sold, you can do that with a lot of things and even further maximize your space.

Buy your supplies now as most garden centers are on clearance for end of the season and it'll be hard some things later this year.  One thing that will save you money and effort later is to begin to get dirt ready.  There are lots of books on how to "home grow" miracle grow type dirt for your gardens, and by starting on a pile of it, through a compost type process, you might have a super-duper garden when you need it!

Good luck.