You can look up a lot of youtube videos, in the day you spent making calls, and waiting for 3rd party to show up, etc.
All apliances will come with instructions , including install and maintenance instructions.
We do it ourselves, and have not gotten shocked, or burnt anything down, or caused a leak, etc.
The bonus is, once you do it one time; it is not as intimidatiing , and has a shorter learning curve the next time.