There’s a point that we make in Grain Into Gold that I don’t think we hit it hard enough. Where are all those prices coming from? There’s a simple formula. Think modern times - what does it cost to get your car fixed? Auto mechanic’s labor plus parts. What does it cost for the plumber to fix your sink? Plumber’s labor (possibly including a fee for the house call) plus parts. What does it cost for a loaf of bread in the supermarket? Baker’s labor plus parts (ingredients) plus transportation plus packaging plus middle man’s mark up. Now in the modern setting, you would have to include the labor of the marketing guys, etc., etc. The fantasy realm is the same. A loaf of bread costs parts plus labor, plus possible transportation plus packaging. For a loaf of bread, there is usually no packaging (the buyer simply puts it in their own basket), there is usually no transport (since the buyer walked to the bakery), and there is likely no middle man, though the baker might be including the cost of his taxes and other overhead in either his labor or an add on cost.
Does packaging matter? Even in the modern age, we’ve all heard that the cost of the cup that the pop at a fast food place comes in is more expensive than the pop itself. (That’s a yes.) In the fantasy era, a cloth bag to carry five pounds of flour will likely cost more than the flour. In some cases, the wooden keg the beer comes in might be more expensive than the beer. You can bet that these people are using the same packaging over and over if at all possible.
The transport situation was covered in Grain Into Gold, but not to my satisfaction. That’s where Coins of the Road will come in. Yes, I know it was likely promised some time ago, but things being what they are, it likely still isn’t going to hit the e-shelves in 2009. (Grain Into Gold is our best seller. People really liked it. To be honest, we’re working our tails off to make sure that it’s follow up is at least as good. That has been difficult!)
Anyway - when you’re figuring out what something cost - the simple formula will always be parts + labor.