What state are you in? I've never heard of a four-digit permit cost. Can you provide a link or any evidence to back this "$1500 or more" figure up?
It seems like you are trying hard to use worst case numbers. The link I provided (here it is again) had prices for various garage chargers all of which are between $450 and $1,000 (none of them are $1,100). As far as installation, if your house was built in the last 30 years then it should only cost around $200.
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In California, there is no such thing as a bldg permit for less than $1200 that I have ever encountered.
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