I was wondering, is an electrical permit needed for every new installation? Or is it up to the customer? Thanks
The only way to know for sure if a permit is necessary is to ask the "authority having jurisdiction" or AHJ.
Example: Here there are some jurisdictions where a panel change is considered repair work and no permit is needed. In another jurisdiction the cost of the panel replacement may decide if a permit is necessary.
Talk to the electrical inspectors in the areas where you are going to work and they will help a lot. Let them know you would like to stay legal and would like their advice on doing so.
There are times when a permit and inspection may not be necessary for the AHJ but will be required to get paid by say an insurance company.