Another option would be to speak with your tax person about the requirements and expense involved in lending the cash to the llc when needed.

Specifically regarding plumbing you could add (depending on your State or Local Laws) "... unless determined by repair person that such blockage occurred during the time Tenant controlled the Premises and due to some fault or negligence of Tenant, specifically excluding blockages caused by roots or backups from the street..."

You can use that for marketing to get deals and then partner with people with money...

I'm thinking about where to invest that money into, and was wondering if the following is possible?

No one can tell you which method is best as it depends on your personal risk tolerance, financial position, etc.

The person I talked to didn’t want to tell me.

There is still money to be made and I think you have a good list of requirements, the pool of areas and properties is small in CA for a buy and hold appreciation. 

It's hard to give directions when I don't know where you are going, where you are starting from, or whether you are walking, riding a bicycle, or driving a car.One thing I do know: do not spend all your money!

We have around 50k to start and we are not sure if we should use our money or should we use other peoples money as that is always what I hear about real estate investing.

Most younger attorneys would probably take a case like that and you don't have to throw good money after bad money.