Upgrading from Free to Standard for just 1 User possible?

Upgrading from Free to Standard for just 1 User possible?

When I try to upgrade from Free to standard to increase the number of Leads I can store, it only offers me the option of having 2 users at $24/month.  I am a one-person company and want only one user on the Standard plan.  Is there a way to buy just storage or a way for one user to be on the Standard plan at $12/month?  

Thanks!