Once you purchase a VPS or Dedicated hosting server along with a cPanel license, you will have a limitation on cPanel account creation according to the chosen cPanel Tier.

cPanel Pricing

VPS Pricing
cPanel VPS Solo (1 account)	$16.88/month
cPanel VPS Tier 1 (5 accounts)	$19.88/month
cPanel VPS Tier 2 (30 accounts)	$27.88/month
cPanel VPS Tier 3 (100 accounts)	$44.88/month
cPanel VPS additional 50 accounts slot	$17.00/month
Dedicated Server Pricing
cPanel Dedicated Server Solo (1 account)	$17.88/month
cPanel Dedicated Server Tier 1 (100 accounts)	$44.88/month
cPanel Dedicated Server Tier 2 (150 accounts)	$56.88/month
cPanel Dedicated Server Tier 3 (200 accounts)	$72.88/month
cPanel Dedicated Server Tier 4 (250 accounts)	$86.88/month
cPanel Dedicated Server additional 250 accounts slot	$83.00/month

How to Change Tiers

VPS Hosting: With VPS hosting, you may choose Solo Tier, Tier One, and Tier Two during purchase. If you need more cPanel accounts, you can upgrade to Tier Three. For further accounts, you can add an additional 50 accounts slot at $15/month by sending an email to billing@namecheap.com.

Dedicated Hosting: With Dedicated hosting, you may choose Solo Tier and Tier One during purchase. To add more accounts, you can switch to Tier Two, Tier Three, or Tier Four. If you need more than Tier Four allows, you can add an additional 250 accounts slot at $70/month by sending an email to billing@namecheap.com.