Shop around, keep costs as low as possible... you're trying to make a name for yourself. Some things require you to take the hit .. all part of establishing your name/brand.
Don't expect to make exorbitant profits from your first few offerings.
Establishing yourself usually comes at some personal cost.
Be open to criticism. Yes, painful but this is how you learn.
Ignore the trolls ofc.
Engagement pays off, this is also part of the learning process.
Cheers
Viz