When we started our vinyl business we spent months figuring out our prices! I cringe each time I see someone ask,"I made this for a customer, but I don't know how much to charge."
Never cut an order without giving someone a price!
If anyone in your area does vinyl or similar items figure out what they are charging. You don't want to over (or under) charge.
When we were figuring out our prices I was looking at another vinyl business's price sheet and it made no sense! They had a price grid and things didn't match up. For example for something 12 inches wide by 24 inches tall it would be $15, but for something 24 inches tall by 12 inches wide was $18.
Our prices are broken down by square inches (for vinyl).
Our minimum price is $3. For everything over 300 inches it is 5 cents an inch.
For something 30" x 10" would be 300 inches and $15.
However, our heat transfer is by linear inches.
It is $1 a linear inch. So it doesn't matter if it is 2" by 2" or 2" x 10", they are both $2.
You can price your items however you would like. This is just how we have done things.