I am NOT a Zoho expert by any means, but I'm hoping that someone here might be able to give me guidance on how to approach solving this problem for my business. I have a Zoho CRM Enterprise account with 2 users (very small business) and can't afford to add more users to solve this problem. Here's what I'm trying to do:

My company plans very small weddings (elopements) for our customers. The business itself functions very much like a general contractor, where the customer hires my company for planning, and we subcontract vendors and suppliers on behalf of the customer.

Each elopement has between 1 and 12 vendors/suppliers that need to be contacted and coordinated. Right now, all of the contact information, notes, deadlines, and payment information for those vendors/suppliers is being dumped into a long description field in the Lead and then converted and updated in the Deal/Opportunity record. Doing everything manually was a workable solution when we only had a handful of elopements like this each month, but now we are booking enough of them that keeping track of the vendors/suppliers and the emails associated with each Lead/Deal is very difficult. 

So, the problem I'm trying to solve is essentially creating a way to track the status, details, and communication with multiple vendors/suppliers (Contacts) as they relate to specific Lead/Deal records. Those vendors/suppliers are not (and will not be) Zoho users. 

My initial thought was to create lookup fields for each different vendor type inside the Lead/Deal modules and associate the contact record for the vendor/supplier using that lookup field. Then I realized that my account only has 2 lookup fields remaining (total) so that isn't an option. I do, however, still have two Multi-Select Lookup fields remaining, which means that I could (in theory) create a linking module and do a many-to-many link between the Deal and the Contact records for all of the vendors/suppliers. This seemed like a good idea until I realized that there's no option for automation on a linking module, which would be the entire point of doing this in the first place - I need to create workflows to fire email notifications to associated contacts and if I can't do that then this isn't a solution to my problem. 

Then I started thinking about using Contact Roles (already in place in Deals) to associate vendor/supplier contacts with the Deal record (I realize I can't do this with Leads) but I realized that it's not possible to create an Action to send an email template to a contact based on their Contact Role, so that won't work either.

So now I'm stuck. I need to find a way to associate multiple Contact records with multiple Deals in a way that allows me to create workflows and send them automated emails, AND have those emails indexed with the rest of the communication for that specific Deal. Anybody got any bright ideas of how I can attack this problem?