I would have to agree with Mark Daguide. (remember I dabble in transfer making).
Heat transfers are great but not for a straight up 760 ready to wear shirt order. Sure, go ahead and get transfers made if you are chillin' and need to do some work to warm you up.

...but seriously, you could be getting 10 more sales mean while and let the screen printer work for/with you.
Small Jobs or Brand fill on demant is what makes heat transfer GOLD.
one more thing, in a perfect world the transfers will be great, your application will be amazing and the customer will be happy.
In a not so perfect world and something goes wrong....you could lose your shirt.
congratulations on getting the job.
that alone is a great achievement.
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