Tenant And Landlord Security Deposit Dispute

I rented a property from a private individual in Placer County, CA, for almost four years. I gave one month's notice, and we had a physical final walkthrough that lasted about an hour. During that walkthrough, the landlord mentioned some minor issues and cleaning, to which I agreed.

However, after two weeks, the landlord sent me an email with a list of over 20 itemized issues, including a curry odor (which was not discussed during the final walkthrough). He only provided estimates for four or five of those issues.

After two months , the landlord sent a certified letter with a $10,000 bill. The letter included an itemized list of issues with charges, but there were no invoices or vendor receipts attached. He is asking me to pay within 15 days.

Below are my questions:

1. Is the landlord allowed to add more issues, such as odor and others, after two weeks?

2. Is it acceptable for the landlord to send a list of damages after two weeks without providing preliminary charges for all the issues? (He claimed that he didn’t receive quotes from vendors.)

3. Is it legal for the landlord to send a letter demanding $10,000 after 2 months of post-final walkthrough?

4. Is invoices and receipts mandatory to submit to me within 21 days?