Thoughts on ZOHO CRM? or others?

Apptivo is zoho's closest competitor. They also have a freemium model, in some cases better than zoho but you'd have to weigh up the features.

Using zoho.crm now for four years with now six users.

It has its benefits and disadvantages. I m using the MailChimp and the zoho.crm plugin, some other features. Works good.
My biggest problem is that the stock quantity is getting screwed up very quickly. We weren't able to figure it out what the reason is. Even the somewhat useless support gave up quickly blaming our workflow.
We are still using quickbooks for tax reasons and don't have the issue there.

You won't be able to build any custom modules like "Payments" unless you have the $40+ version. We just switched from Zoho CRM to Salesforce but Salesforce is also $105 a month per user so not in your budget. Zoho was good, the interface was just very basic and plain. Check Knack as well, it's more like a build it yourself database but it's pretty easy to use if you're even remotely technical.