Recommendations for a storage shed kit?

A lot depends on what state you are in and what the building code says.

I've got a resin shed and it's held together good except from one freak microburst that disassembled it. I put it back together with some sturdier fasteners at key points.

I also have one of the sheet metal variety in Arizona that's held up for close to thirty years. If you get one of those, have a helper on hand and pick a still day. They're rugged enough when they are assembled. I put mine together on New Years day. My friend had a major hangover and the wind picks up after sunrise in Arizona. Wasn't fun. A power screwdriver would be good too.

Be careful how you build.

Where I live, if sheds have footings and a concrete floor, the square footage is calculated and the structure is taxed at the same rate as a house.  OTOH, build a pressure-treated floating deck and then build a shed on top of that and you'll avoid additional property taxes

Comes down to money versus ambition. I bought a complete shed, 12 x 16, and had it delivered, set in place. Done, but cost more than a kit. Much easier and faster though.

Yes, same for me. Therefore, shed will be raised on 4-6 (or however many needed) individual concrete blocks. No poured floor slab. No foundation.

Same when I put mine in. Did need a permit though, and a sketch of location as it cannot be within 5' of the property line.

And for many hangers-on on this list, much better constructed as well.

Precast concrete sidewalk slabs on grade also work without tax or inspection issues (at least in most places) Anything that makes it not a "permanent structure". Limited in size though - 100 or 120 square foot maximum is common. Rules out the "portable garages" in many areas.

Do you have enough room to do a tilt up? (need wall height and a little more in all directions)

See that is what I am talking about. In Florida your shed has to meet the wind code and anything simply up on blocks is illegal (AKA wind borne debris) ALL sheds require engineering and a permit. They make prefab wind code sheds but they still need an engineered tie down. We see what happens when you don't every time some little dust devil or minor windstorm goes through a northern state. (Like "not quite a storm" Sandy).

What are you tilting up?

Concrete walls poured locally.

that sounds like a 'hold my beer and watch this' moment.

On something as small as a shed you could probably DIY.

There is also ICF construction but you'd need to hire a concrete truck to pour, I would think.

Either one would give you a very solid shed.

My experience years ago was putting up one made of aluminum. I had gravel as base and covered it with exterior plywood. No permit needed but that was years ago and local regulations change.

Today I might browse the big box stores on line to see what they have to offer and check all reviews.

Might also mention that neighbor had one made by the Amish in nearby PA and shipped in and said he saved a ton of money.

I've never seen it. I'm not arguing, just saying I haven't seen the technique.

"Tilt-up construction allows general contractors to build a wide range of commercial buildings more quickly and with lower construction costs than what is typical for traditional masonry construction projects. Texas, California and Florida are currently the most popular states for tilt-up concrete construction. In northern states with more severe winter climates, Precast concrete buildings are more popular."

That explains a lot since I've lived my life in the north, but I haven't seen precast around here either.

Cant see that working because of the curved hull required.

Not convinced it would work for a barge either, hard to do the joints.

Sure, but that's not YTong concrete. Its autoclaved.

you just need a big enough kiln. The panels I was looking at were 8x16 feet. That could have been a 16' boat.