If I understand that you are talking about tomato sauce, then you do not need a pressure cooker. One cans acidic food like tomatoes and most jellies and jams, apple butter, fruit pie fillings, crab apples, etc. in a boiling water bath. All you need is the jars, rings and lids, and a pot big enough to boil them in. A large cheap ($5.00 ~ 2.5 quid) aluminum stock pot bought at a discount store is what I use. You'll need a rack that fits it (made mine from an old grill, I've used metal fencing in the past, but do not suggest galvinized materials). In theory nothing gets into the jars, but still... Also a pair of jar tongs to move the jars in and out of the hot water. If your boyfriend is handy he can make something that will do once he has seen these. However, from a safety standpoint (don't want to drop those hot jars!) they are worth buying. With this kind of set up, your canning will pay for itself the first time you do it.
Some sites: http://frugalliving.about.com/cs/canningfood/a/081302.htm
HTH- I love canning, and usually find many people more than willing to let me pick fruit etc. that is going to waste in their yards.