Dog, that's just under four times what Max Dahl charges for a custom cover made to fit your boat(s). His price, I repeat, is $89.95 + $10 s&h. I have two of them. They are flat out excellent. This is his main line of work.
even Danuu ready mades at $125-$175 (depending on length) are a far better deal.
IMO Sunbrella is overkill and so are the total charges your guy is quoting.
:::shrug::: your money, your boat.