Since I'm WELL AWARE that it doesn't require that much input to farm, I emailed my favorite farm guru, Sharon Astyk. In the email, I asked for a rough estimate of what a simple set up would be, not counting property.
-- a couple of pigs
-- a dozen chickens
-- a couple of goats
-- fencing for the animals
-- a hoophouse
-- a farm building or two
Her reply was both thoughtful and in-depth. She warned that this was an exceedingly rough estimate, as it's difficult to judge such things in the abstract. But, here's what it amounts to.
Two pigs - I don't buy pigs, so I'm less sure of the range of farm prices for young shoats, but let's say you buy two pigs, a sow and a boar, for $40 apiece - it could be more in a more populated area, but I've known people to get them for that. That's $80. If you have a good source of scraps locally, you shouldn't need to feed them any purchased feed, just a mineral supplement which you can get for $5 every two months. But that requires a lot of regular scraps - so maybe figure $25 per month in feed for six months for the boar and year round for the sow.
Again, I'm less certain about the figures on the pigs because we don't raise them, but I am pretty sure that at 6 months, you can breed the boar and sow, and then butcher the boar. Hanging weights on most conventional pigs are maybe 80-100lbs of pork, although it could be more or less. With vaccinations and mineral, you spent a little over $200 on your boar, and may get your pork back for as little as $2lb - you could sell it for more, of course. If you didn't have scraps, the cost of production might be much higher, but still lower than buying the equivalent. You'd either want to build a smokehouse or buy a freezer to store your pork, and my guess is that either one will cost you 4-500 dollars.
Also in that equation, you'll get next year's pork largely for free if all goes well - average pig litter is 4-8, so figure 6 pigs for next year. with a monthly cost for maintenence of about $30 - but it could be more, again, especially in the winter.
Housing and fencing are a bigger deal for pigs than chickens - pigs are *strong* - it doesn't have to be big, but it does have to be sturdy. A small barn suitable for pigs and goats together would probably cost you $1000-2000 to build, maybe even more if you need a lot of permits, or can't do any work yourself. If you are pasturing your pigs, you'll probably want electric netting to keep them in - about $200 if you are moving the pigs around every day, more if you want to be able to go away - 600, say. If you want woven wire perimeter fencing that's more, but we'll assume you'll go cheap and electric.
Initial start-up: $2000 (animal, housing, fencing)
Yearly input: $180 (food)
Average yearly gain: 80-100 lbs. of pork per animal butchered, selling shoats, stud services perhaps
A dozen chickens - bought from the feed store as chicks, probably $25 plus feed. Feed costs depend on whether you want organic or not, and how much pasture and scraps you can get. 12 chicks take a long time to go through a 50lb sack of chick grower - probably 2 months, and that will cost you $18 organic and $13 non. Then you might go through a bag a month, plus scraps and pasture for 12 hens at the same prices. Could be a bit cheaper, could be more if you don't have many scraps or pasture.
Remember in that calculation that 12 hens will give you 1/2 dozen eggs a day average year round - 3 1/2 dozen a week. Assume you keep 1 1/2 for yourselves, if you buy the organic and have a good source of scraps, you can charge $4 doz in most outer areas, more in the city. But let's call it that - so you could sell 8 dozen a month at $4 each - and make back cost of feed, plus get your own eggs free. But that depends on how good you are at that sort of thing.
You don't need any fencing for the chickens, just housing - they can range around. For housing, you could probably build a functional chicken coop out of shipping pallets and plywood for under $50, although you could go for greater aesthetic value and also greater longevity and spend several hundred. It would partly depend on your skills and also your neighborhood. If you have to pay someone to build it or buy a pre-made coop, think 700-800 for anything really nice.
Initial start-up: $2000 (animal, housing, fencing)
Yearly input: $120 (food) + any repairs
Average yearly gain: 890 dozen eggs, sale of chickens, sale of eggs
For goats - if we're talking big goats, the fencing costs are much higher. If you want little ones like mine, you can get away with woven wire or stock panels, or electric netting easily enough. The big ones can jump over that too easily. So let's talk mini goats.
Two does in milk would cost you 600-800 dollars. You'll get the best price if you buy first fresheners, who have just kidded for the first time and aren't proven in the milk pail (ask about their genetics and their mother's milking) or if you buy an older doe with a few more years of kidding in her. If you can get one of each - a good older doe and a first freshener, you'll probably maximize youth and milk.
For two does, you could easily get away with one roll of electric netting and just move them every few days, so let's assume that. Again, that's about $200. You could let them roam too, like we do, but you won't want to do that if you go away, so having some fencing is essential.
You will also have to buy a winter's hay for them - two does would probably eat 50 bales over the course of a year (that's a high estimate, but let's bet high, since they waste some) - at $4 bale that's $200. They would go through a sack of grain a month - $20 organic, $15 non. They also need a bag of loose mineral every 2 months $5, and vaccinations once a year $25, vitamin E when they are knocked up $5 month for both, and you'd need to invest in milking equipment.
If you use jars and just by the filter like we did, and want a manual milker (useful for being able to go away) you'd probably need to spend $100 on milking start up equipment and you might need to pay as much as $300 to build a stanchion. You could probably build one yourself for $50 if you are handy, though. Kidding equipment would cost you $150 - most of which is amortized over a lifetime of use. Without a buck you'd also pay $20-50 per year for stud fees for each goat to get them bred.
Each year you'd get two kids worth $250-400 if you are registered, $100-200 if not. You'd also get an average of 3 quarts of milk a day for 10 months per year. In most states you won't be able to sell it, although you may be able to use it for barter, but you can do the math for milk and cheese and figure out what the equivalents are for you, whether you do organic or not.
Initial start-up: $1250 (animal, housing, milking, kidding equipment)
Yearly input: $475 (food, vaccinations, stud fees)
Average yearly gain: 225 gallons of milk, $200-400 in kids
A hoophouse can be made for as little as $100, but I doubt it will hold up long to a cold climate snow load - I'd estimate $500 for a small one - maybe $300 if you are handy and good and building. They could cost up to many thousands if you want a big one.
Initial start-up: $500
Yearly input: any repairs
Average yearly gain: season extension -- fresh veggies longer, earlier start to seeds and veggies
Where are you willing to live is one of them - even barring the broader property question, that has implications for how much it will cost to acquire buildings. There are places where old farm buildings will be part of the property for no more than the land would cost - and places where it would be very expensive to find someone to build them.
How handy are you? How good are you at building things in general? If you can do the work yourself, it will obviously be a lot cheaper. If you are good at scavenging, you may be able to get a lot of your building materials for free by taking down old buildings or haunting building sites - but one of you has to be good at this sort of thing.
Initial start-up: $0-1000
Yearly input: repairs
Average yearly gain: storage, useful space, more space for animals perhaps
Initial start-up: $5750-6750
Yearly input: $775 + any repairs
Average yearly gain: 80-100 lbs. of pork per animal butchered, selling shoats, stud services perhaps; 890 dozen eggs, sale of chickens, sale of eggs; 225 gallons of milk, $200-400 in kids; season extension -- fresh veggies longer, earlier start to seeds and veggies; storage, useful space, more space for animals perhaps
So, it looks like I was right about THIS argument. :-P