I want to lick plantnerd in the face Amazing suggestions!
I will amend her suggestions and say fart tearing up the grass, it sucks a lot. Lay newspaper down (which you can scavenge from recycle bins or pretty much wherever) Then water the newspaper or it will blow away.
I can't stress enough how amazing leaves are! I told one of my neighbors that he could blow his leaves into my yard, that I needed them for the garden. You would have thought it was Christmas! Bagging is the hard part for them (and this is the first year we haven't had curbside so my neighborhood is grumbling!)
Also, I am reading up on soda bottle container gardening (topsey turvey style) but like you, I'm not trying to spend a fortune on dirt. I think I may have to go around and ask about broken bags!
Also, horse crap!! I grew up on a horse farm and well rotted manure is gold. It has to be old old old, but horses, goats anything like that, most farmers have a system for the manure and wish more people would come take it away.
We are in totally different zones (I'm 5, you're like 8?) so I can't really give you advice about where veggies like to grow. In Southern Ohio, cucs do well in containers. They like the heat! Also peppers, eggplants (which I can ONLY grow in 5 gal buckets!) and tomatoes. Lettuce also, it will grow well in containers. Or upside down 2L bottles! Anything that will hold dirt will hold veggies.
Be mindful of water. Containers dry out really fast. I like to put single serve plastic juice bottles (I get them from a recycle bin on my road, I don't know what they are) put some rocks (like 5 stones) in the bottom, jab some holes, fill with water and set it in the container. The water will leak out slowly and keep things moist! Plus you can see with your eyes the container is empty and can refill!
And potatoes! You can get burlap sacks from a REAL coffee house (not Starbucks, someone who is a coffee roaster) put a spud in, and fill with dirt as he grows, rolling the sides up as you go. When you are ready to harvest, kick it over (onto a tarp to save the soil!) and bam. Potatoes everywhere.