Free/Low cost CRM for single user

I’m looking for a free or low cost ($20 or less a month) CRM to track clients. The company I’m with is very old school and only uses paper lead cards. They have a great product and pay plan, but with anywhere from 500-800 leads a year I feel like stuff may slip through the cracks. Anyone have any suggestions for a CRM with the following characteristics:

1) mobile friendly

2) reminder tasks/ability to assign activities to certain dates. Example: check in on funding October 2nd 2024

3) must be able to track 1,000+ clients

4) must track name, phone number, email (obviously)

5) must have note tab assigned to client so I can outline their product parameters and wants vs needs.

6) automated text or email a plus

7) must cost less than $20 a month.

8) only needed for myself currently, but ability to add one other user at a low cost is a plus.