I want help in mutation of property in new delhi

Hi, my father in law passed away a few days back, he has left a notary will with witness signature. I am looking to get some company that can get us the property mutation done. 

1.Can you please suggest any such credible company in new delhi?

2. Is is best to do it ones own self? What is the procedure? Course of action?

Thanks,

Siddharth