But is it essential to buy expensive gadgets and pots? Nope. Think about it - the essentials of gardening are seeds (then seedlings), something in which they grow, something to hold that in which they grow, water and sun - and perhaps some additional nutrition as the season wears on and the plant exhausts the nutrients in its immediate vicinity.
Seeds are pretty inexpensive, and even in many cases free - if you have friends who are avid seed savers and have far more than they need. If you want to start with seedlings, there is some cost involved, though, again, savvy shoppers can find good deals. The "dirt" - that is an area that I don't want to skimp on if growing my plants in containers (poor drainage and/or disease can end many a gardener's dream of a bountiful harvest).
As to what to put the soil and seedling in, you can purchase expensive containers and pots at stores or in catalogs, or you can go with the least expensive option, or reuse containers that shrubs or trees or perennials come in. I've been known to stop by the side of roads to gather nice large black plastic pots that either flew out of someone's truck, or were tossed there by someone who obviously didn't need them. Then there are Grow bags - inexpensive, reusable, and pretty easily portable, as long as they aren't too large.
I've found that saucers aren't needed, and color, though it could have minor effects, isn't really all that important. I think it is wise to avoid clay/terra cotta, due to its porosity, hence poor water retaining ability. Drainage holes in the bottom are essential. Bleaching prior to use is recommended, in case there are soil borne diseases embedded in the walls of the container. I've found that plants in containers sitting right on my concrete driveway, perhaps due to the baking heat of the direct sun, out grow (in speed) and, in the case of eggplant and peppers especially, out-yield those grown in the garden soil.
Below are an array of the different types of pots I am using - 10 to 15 gallon large ones for indeterminate tomatoes, smaller 5 gallon pots or grow bags for peppers, eggplant and dwarf tomatoes, and very small - half gallon - black plastic pots in which to grow hot peppers sufficiently large to give them a good test.
I hope that this is helpful to you!