It can be expensive, yes.
If it's non-selvedge, the price would start at $40.
If it's selvedge then the price may start at $90.
The style would matter too. If you want just regular pants or cargo pants.
So the style and the fabric (selvedge/non-selvedge) are the things that affect the price.
"A selvage (US English) or selvedge (British English) is a "self-finished" edge of a piece of fabric which keeps it from unraveling and fraying.[1][2] The term "self-finished" means that the edge does not require additional finishing work, such as hem or bias tape, to prevent fraying."
from Wikipedia
So selvedge denim runs on shuttle looms and it is tightly woven to make it stronger. Not taking anything away from non-selvedge denim but selvedge denim are far superior. More information about selvedge denim on the world wide web.
Think of me as your friendly tailor. The average time I complete making a single pair of jeans is 6 hours. However, I am just one man and I make the pants in order of the item it was received. So if you are number 16 in the queue, then I can maybe start working on your pants 2 or 3 weeks from the time you complete the payment. Don't worry, I will keep updating you regarding your order and you will hear from me within 24 hours if you will send me an email.
If you're in a different country than mine, aside from the price of the item, you will also handle the shipping cost and any fees in your country.
My process is easy. After we agree on the style, measurement, and price of your order, I do these things in sequence: