None of their livestock needs any bedding, nor bought-in forage. Nor contractor costs for making hay. Dan's just posted; I'd assumed the £150 was cake, but maybe it's winter forage. I guess you can get straw pretty cheaply up there? But there's still haulage from the east side...
They expect to have a beast to slaughter every 12 months, rendering 200kg saleable meat, starting at month 8, having initially spent only £1000 on a house cow 'and followers'. Must be a big breed for that amount of meat; I don't know where they'll get an in-calf cow, a weanling and 20-month old, all for £1000. However, once they're rolling, there'd be no further purchase costs, I guess. I'm dubious about rearing a beast that size off 6 acres that's also got all this other livestock on it.
No figures for packaging their meat or eggs.
I haven't worked through the pig numbers, but I'd agree that £18000 income for £3000 feed (and no bedding costs) sounds optimistic.
General running repairs £50/month. With 150 hens, up to 30 weaners, the house cow and two followers, on 6 acres, you say? In Aberfoyle.
Well, if they make it, that's a model that many of us might like to follow!