Great point, Nell. Hybrids are sterile.
My green beens I allow to grow on a fence in the garden. I harvest all of them when they are about 4-5 inches long, blanch them for 3 minutes, ice them to stop the cooking process then freeze. I can harvest every other day for beans. If you have wild animals or dogs then you want to stay away from bush beans. They have little tiny hairs that will collect and hold animal hair. So if you dog walks through the garden your whole crop of bush beans will be ruined. Climbers don't have the hairs but most do have a string (hence, the name string bean) that runs down the seam of the bean. If you want until they are longer than 4 inches the string will be very tough and you will have to remove it from each bean.
Squash or cucumbers or zucchini can be harvested and you can dry and save the seeds if you like.
My tomatoes I buy the plants and I look for plants that will produce throughout the summer. I look for an early bearing variety, mid variety and late so I have tomatoes all season. I have fiberglass fence posts that I use in the garden and the tomatoes are staked to the posts to grow. You can also blanch tomatoes and freeze them as well for use in spaghetti sauce, etc.
Look for heirloom plants if you want some of the best flavors. Today's plants have been engineered to produce pretty fruit at the cost of taste. Heirloom plants are generally the older generation plants that might produce an uneven or uglier fruit but has a much better flavor.

