Is it necessary for immigrants to find an immigration company?

I have been to many immigration companies, and my sister accompanied me. Recently, I went to an immigration company, and I was very impressed. It seems to be called Pacific Jiada. This company is quite large. Because my sister's case was troublesome, many immigration companies refused to take it, so I gave it a try. I was received by a foreigner as soon as I entered the door. Later, I learned that I am a foreign lawyer, very professional, and my service is very good. I helped my sister analyze her actual situation and helped her a lot.