Back when we signed our contract (Jan/Feb time frame last year) our contract required 1/2 down when they showed up at our house first day and the balance when we got PTO, not at time of inspection. I know at some later point people did not have to pay any upfront payment and Tesla would front the cost for all the work and equipment and require only a 1 time payment — but now after inspection when their workers were done after which they’d submit application for PTO to the utility.
Guess it would have been nice to sit on all our funds for months longer as the 1 time-payment people got to but It was what it was at the time we signed our contract. For the 1-time-after-inspection people, Tesla is laying out all their costs and labor upfront with no funds from you with the legal requirement you pay upon inspection. They did the work to get inspection passed and trust you to uphold your financial end and it’s not like they aren’t going to come thru with filing your PTO. PG&E took a few weeks but less than 30 days to review and grant us our PTO.
FWIW, for my 2 powerwall install added to existing solar, I paid $100 up front, then the balance after inspection but before they would submit for PTO, so I believe I fall into the "1 time payment" as I dont consider $100 deposit on an invoice that cost over 18k a payment.. even though it technically is one.
In any case, @Carbonfiber I hope you get PTO soon. For me personally, putting up with the idiosyncrasies tesla had was worth the difference in price between them and someone else (which was way more than 10% in my case). For 10% I might have gone with a third party as well.