Can I install a wall-mounted gazebo over vinyl siding, with plinths to account for an un-level slab?

Can I install a wall-mounted gazebo over vinyl siding, with plinths to account for an un-level slab? I would like to install a wall-mounted gazebo to the back of my house with vinyl siding, where there's an existing concrete slab. I enjoy DIY and feel mostly up to it, but am unsure of two things: (1) the difficulty of ensuring all the wall mounted brackets tie into a stud and (2) whether using concrete plinths of varying height to account for the slab being slightly un-level will be effective / sufficiently stable. I may hire it out but would also want to be able to ensure the work is done properly, so i wanted to seek input here. Re #1 (attaching the brackets to the side of the house), my understanding is that we would need to cut the vinyl and use heavy anchors to tie the brackets directly into the house (rather than thru the vinyl, crushing it), and that we would need to ensure they are secured to a stud. If there's not a stud where we need it, we would have to cut more vinyl and use a ledger board secured to a stud(s). We woudl then have to seal everything with proper flashing to prevent water intrusion. The gazebo I want has a bracket in the center at the top, as well as along the two posts at the corners against the house, so unlikely we'd have studs everywhere we need them, resulting in a decent amount of extra effort to tie into the studs and potential challenges sealing things up without it looking weird. Am i properly understanding generally how the process should go, or am i missing anything? Re #2 (plinths for leveling), since the concrete on one side of teh gazebo is ~1" higher than on the other, i'm thinking of making 15x15" concrete plinths that are at least ~1" high and then with extra height to bring to level where needed. This way the ~3" expansion bolts for anchoring will grab some of the slab underneath the plinths as well. I anticipate the plinths being slightly more difficult for the posts that will go right up against the house (eg where i've drawn the red arrow in 2nd photo), but doable. Does this sound like a reasonable plan that will be effective for stability, or am i missing anythign here? A detached gazebo seems simpler (also wouldnt require a permit), but i think this would feel much more natural since at most we'd be able to put the detached one about a foot or so from the house. Thank you!