I'd suggest the Topsy-Turvy planters. Not much heavy soil, no drainage problems, easy to maintain, and they do a good job on both strawberries and tomatoes. They wouldn't take up much space, and she wouldn't be left with a container full of soil in the winter.
I've also experience with using soil inside. Mine had house-gnats and didn't drain properly. Without consistent full sun for many hours a day, the soil in containers tends to dry out on top and remain wet underneath.