is there a way to easily set cost for AC charging

I am relatively new to using Teslafi and I am bothered by it not knowing the cost of AC charging at destinations or public AC chargers near my home.

I found the way for updating the cost of home charging ( which I can't use because the parking I am renting does not have chargers ), but I have a hard time updating the cost of each charge or the cost per kWh.

Would it be possible to just assume a standard rate per kWh for AC charging somewhere instead ?