Estimation only for 20,000 users (for a total transaction of...

Estimation only for 20,000 users (for a total transaction of $10,000)
Annual (Monthly fee) from 20,000 users
$30/(user × monthly) × 12 month = $360/(user × year)
$360/(user × year) × 20,000 users (merchants) = $7,200,000/year

$1 from Customer transaction $100 for a merchant.
If a total amount of transaction for a merchant per year : $10,000 ($100 transaction fee per year)
$100/(merchant × year) × 20,000 merchants = $2,000,000 / year

(Monthly fee + transaction fee for $10,000)/year = $9,200,000/year

Hardware ($150-250) ???

Excluding hardware: $9,200,000/year