Pricing your handmade merchandise can be tricky. The bottom line is to remember that you're doing this for a profit. If you spent $10 on materials, then you better be charging more than $10 for your pieces, or you won't be able to do this for much longer!
Also, there isn't necessarily a Right or Wrong way to price your stuff. You will find what works for you.

You've made a really cool top to sell, but you're just not sure what to charge for it. Here we go-

main fabric - $8 a yard
lace - $2 a yard
elastic - $1 a yard

For this top, you used 1 a yard of the main fabric ($8.00)
2 yards of lace ($4.00)
1 yard of elastic ($1.00)

Your total for materials is $13.00

Let's see about labor. You'll need to decide on your hourly wage. We'll use $10, which I think is the absolute minimum you should be paying yourself.

$10 an hour

For this top, you spent 2 hours working on it ($10 times 2 hours), so $20.00 is your labor cost.

Add these together ($13 + $20) and you get $33. You can use $33 as your price, but you're technically not making a profit. Sure, you get to keep that $20 for labor, but your wage is NOT your profit. When you're first starting out, it makes sense to keep your profit low (which in turn, keeps the prices low). But when you've got a decent customer base, don't be afraid to increase your profit margin... and your hourly wage, for that matter. Especially since over time, you will probably become quicker at assembling your goods, so this same top may only take an hour to finish.
Anyway, for this example, we'll tack on $5 for profit to make the total $38.

This is your wholesale price. If you're selling your goods to a store, this is the price you use. The store will then mark the price up, usually at least doubling it. If you're consigning, remember to compensate for the consignment fee (which is usually anywhere from 2S0-50% of the selling price). If you're selling your stuff directly to the public, you'll want to figure what your costs are as far as the upkeep of your shop. If it's a bricks and mortar store, you've got rent, utilities, insurance, etc to consider. If your shop is online, remember to account for your payment processing and selling fees, hosting, domain names, etc.

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