We have a web based software and prospects enter our CRM in 2 ways and we send out a series of emails

1) Leads from Trade Shows, Web Form, Prospecting, etc - those of course go to leads

- They are sent emails every 5 days, which we have setup now via workflow automation and time based actions.

2) Users sign up for a Free 30 Day Trial and are put into Contacts

- They are also sent automated emails at certain intervals, also setup via workflow automation. For example upon signup (welcome), at the 3 day mark, 7 Day, 10 Day, and so forth until their trial is completed.

Yesterday we received an email that the # of time based actions were exceeded and I do understand the limits.  My question is, given the scenario(s) above and our sales processes, what is the best way to set up these automated emails and be within the daily limits that Zoho allows.

By the end of the year we will have 3000 prospects and 200 Contacts.  I have read quite a bit on the support side of Zoho but I am still confused as to which process or combination of processes will work best for us (Workflow Rules/Time Based Actions, Auto Responders or Campaigns)

Any links to "How To's and Setup" would be helpful as well.

Any input would be greatly appreciated and thank you in advance for your time.  I appreciate it.