You need to file a Motion to Quash if you were not properly served. Or you may be able to file a Demurrer if they sued the wrong party or you...

Amend a claim or file another lawsuit?

If the unjust enrichment is related to what you are already suing about, then amend this lawsuit and raise this new issue.

In what fashion would I respond to the defendants and the court to overrule a demurrer?

You'd file an opposition, but it's impossible to give you specific advice without having reviewed the pleadings. A full consultation would be...

Is it appropriate for the spouse of a defendant to serve papers on the plaintiff's lawyer or am I too close to being a party?

Anybody who is over the age of 18 and not a party can serve. So yes, you can serve documents here.

How do I begin the process of addressing this with the seller & real estate agent?

You may have a failure to disclose claim here, depending on what your documents say and what the agents knew. A full consultation would be...

When can i sue him? Or wait to be served?

You can file a lawsuit against the landlord now. A full consultation would be necessary to properly advise you.

Any advise for the above question

You have to register a corporation, and then you can file an S Corp election with the IRS to make it an S corporation.

Can someone help me with this? WHAT GOOD ARE LAWS IF NO ONE IS ENFORCING THEM? Are all attorneys Pro-Employer?

Sorry to hear about your situation. We cannot solicit clients on here, but you can contact us directly. A full consultation would be necessary...

Assuming you are an at-will employee, yes, this is legal for your employer to do.

How do I serve the amended complaint to the Defendants? I am in Los Angeles County and the Defendants are in Orange County.

If you have already personally served the original complaint upon these defendants, then yes, you can serve by first class mail.