It doesn't take much. You need:
1. fencing - $300 - first a physically fenced space to train them to electricity and then ideally a larger area to let them out to graze. Cost for a good (>1.5 Joule, ideally ≥6 Joule) charger is about $100 to $200. Step in posts or insulators maybe $50. Polywire $30 to $60. Ground rod $10. Misc $20. That will give you a decent fence that will likely last for five to ten years. For the physically tight fenced area pallets work great. Put a hot wire inside them on insulators at low and walking nose heights.
2. food - $150 per pig in bagged small quantities last I knew. Grazing can greatly decrease this cost. Good free pre-consumer food like dairy and such can also greatly decrease the cost. Food is the big cost on pigs.
3. piglets - $100 each around here right now if you can find them. Cost varies greatly with location, age, season, etc. Fall is the best time to buy pigs if you're looking to save money on the piglet cost. They grow fine through the winter although they will eat a little more as they need more calories for warmth.
4. hay or pasture depending on the season is a good thing.
5. "Small Scale Pig Raising" by Dirk van Loon - the best book I've seen. Get it. $10 or so.
It is just about as easy to raise four as it is to raise one and by being in a group they grow faster because they are competitive feeders. By raising extras you can sell them and amortize the costs a bit for your fixed things like fencing.
Housing doesn't need to be fancy. A lean-to works great.
See this:
http://sugarmtnfarm.com/blog/2005/08...-for-meat.html
Cheers
-Walter
Sugar Mountain Farm
in the mountains of Vermont
http://SugarMtnFarm.com/blog/
http://HollyGraphicArt.com/
http://NoNAIS.org