Plesk Starter

1 GB Diskspace
10 Email Accounts

Plesk Basic

2 GB Diskspace
Unlimited Email Accounts

Plesk Standard

5 GB Diskspace
Unlimited Email Accounts

Plesk Business

15GB Diskspace
Unlimited Email Accounts

Plesk Enterprise

25GB Diskspace
Unlimited Email Accounts

Plesk Free Trial

14 Days Trial.
Ensure you upgrade after fully testing as it may terminate upon 14th day.