Does the Aoxun 10x12 shed include a floor?

No. It is a panel-and-frame building, so you set it on a level base such as a concrete slab or pressure-treated platform. A solid, flat base also keeps the doors aligned.

Is aluminum better than a steel shed?

Aluminum won't rust through like untreated steel, which matters in wet or coastal areas. Steel is stiffer and heavier; aluminum panels are lighter and easier to move but flex more.

How much can it hold?

The 10x12 ft footprint gives about 120 sq ft of floor space, enough for a ride-on mower, bicycles and shelving. The description notes mounting positions for internal racks to use the height.

Will my things stay dry inside?

The sloped roof sheds rain and the vent openings improve airflow, which helps with condensation. In very humid or windy, driving-rain conditions, add a raised base and keep items off the floor.

Yes. The double doors are described as lockable, so you can fit your own padlock or lock to secure tools and equipment.

How hard is assembly?

It is a full-size shed with many panels and fasteners, so plan on a day or more with two people. A level base and a helper make the roof and door alignment much easier.