I’m a new landlord in CA and missed the 21 day window to return the security deposit (I thought I had 30 days).

I would want my money to be secured by a promissory note and mortgage on the property in question, and thanks to the advice from some on here, if the property in question isn't enough to cover it, I would need to attach a lien to other property to ensure I can get my money back. 

for sure that is always an option, right now i want to connect with more actual private lenders that want to move their capital at 11% secured by real estate 

Non-recourse loans are typically more common with large-scale commercial projects or through institutional lenders, but most lenders prefer recourse loans where personal guarantees are required.The reason most loans are recourse is that it provides the lender with additional security.

I spoke to a gentleman yesterday who put 400K into a four unit in the city and his first tenant in the one unit bounced their first month's rent and security deposit checks.

Have all your ducks in a row so you can move quickly on securing the deal when you do find the right one that the numbers work on.

LL Flooring, formerly known as Lumber Liquidators, is closing all 430 of its retail stores after failing to secure a buyer during its Chapter 11 bankruptcy process.

Security deposit amountYou can find plenty of examples by searching for "tenant estoppel certificate doc" or exchanging "doc" with "pdf" for more options.Here is an example and explanation: Sample EstoppelSome have a lot of legal jargon but this document does not need to be so detailed.

It sounds like a smart way to build equity and stay secure financially.

They try to steal sensitive information including social security numbers, banking information, birth dates, etc.