Presuming that you are building it rather than a premade, since you continue to mention lumber prices.. and sure, I suppose if you order a premade.. they are quoting you based on then lumber prices.
Do you already have your workers lined up, or you building it yourself?
While I have nothing against buying pre-prepared (kit would have been more likely than a premade. Access is tricky), I couldn't find a design that was quite the way I liked. So self-built it is. Wooden boxes are not exactly rocket science after all.
Nothing like maintaining symmetry with the neighbor. #nohomo
It may be a little taller
I will tell you years ago say 1994 I built the sheds. They lasted til now.
But with the ability to get one pre built matching my siding and my roof.
I let them do it.
Building the bluestone pad was about 800 and 100 for the poison ivy treatments.
I was more sore from the poison Ivy then I was from moving 4.5 tons of gravel into place.
So 900 and three days time for the pad.
I also had a tree guy cut a few trees 🌳 but they were going shed or no shed.
I got a 1500 estimate for the pad so I save 600 bucks.
I killed all the poison Ivy in March 2020 when we put the white vinyl fence in.
I used a shit ton of roundup and it never came back,
But digging the dead roots out to level the ground is what gave me the poison ivy.
The plants were dead for more than 18 months. Still fucked me up.
worst case I have had since I was 11 years old back in the sixties .
I will end up with a second one and have a stone patio put in the center of them.