Yes, you can legally sell it, assuming the artwork belongs to you and was given to you by your mother in law.

Does this count as proper service? If not, how do I let the court know?

Yes, it is proper service............

What is there for me to do because I am very unhappy

You can sue the contractor for breach of contract and/or report him to the CSLB.

Is it legal for me to do the work myself or am I required to hire a licensed contractor/gas fitter?

If it is your property, sure, you can do it yourself.

Is working me only 3 1/2 hours, 4 at the most, legal? What is the minimum amount of hours you have to work a week?

Assuming that you are an at-will employee, there is no minimum number of hours you need to be scheduled for per week or per any time frame.

General contractor violates state law and lien on my property

Yes to both of your questions. You can also file a petition in court to expunge the lien and have the contractor pay your legal fees if you prevail.

Am I personally liable? how do i protect myself immediately? What kind of lawyer? And how much money will this lawyer cost me?

No, you shouldn't be personally liable under this scenario unless you're a party to the contract with the vendor. Typically, only the company...

What type of lawyer should I seek? Will they accept payment from the money I recover? How much would this process cost me?

You need a business or debt collection attorney. A full consultation would be necessary to properly advise you.

You can file a lawsuit for retaliatory eviction, habitability violations, and related claims. A full consultation would be necessary to...

Can HR put me on administration leave and wants to reopen a complaint case that was resolved. I was on med.leave at the time .

Assuming that you are an at-will employee, yes, your HR department can do this.