When can I send a 10-day notice to quit in North Carolina?

[Noureen A S.]

New landlord here... After researching, I'm still struggling to understand the allowable late fee, 10-day notice, and eviction timeline for the state of North Carolina...

1. By law (in NC), you are not allowed to collect a late fee for rent until 5 days after rent is due.... is that correct?
2. On which day would I be allowed to actually mail/post/serve a 10-day notice to quit? The 2nd? (since rent is technically late on the 2nd?)

The day after rent is late, I plan to mail and email a 10-day notice to the tenant (or is email a bad idea? Do any of you email as well as mail? Or do you just post the 10-day notice on the tenant's door?)

Thanks in advance!