We currently use a Google Calendar to book appointments (this is the sale) but we don't generally track where leads come from, hence we are looking at Zoho CRM.

Our leads come from our online contact form, online booking form, direct email, and calls. I appreciate how online contact forms and booking forms can be easily integrated into Zoho, but how about customers that book through direct email and by phone that just book an appointment? I would like the simplest way possible just to link an appointment to how the lead was generated (asking the customer how you got our phone number then adding this sale somewhere on Zoho?).

Most customers only come once, so I'm only interested in following up leads, and generating reports rather than generating leads/opportunities through the CRM.

Also as a side note - is there any use in linking the appointment calendar with the CRM? It is worth mentioning that different types of appointments cost different amounts, so an integration with the sales aspect may be useful information on the reports. Should I go further and have all customer info on Zoho and link appointments back to a Zoho contact?

I thank you for any advice