Garden house, what should one pay attention to?

how about metal, are they really that loud in the rain? I thought you had to paint wood regularly or annually

Annually is a misconception. Regularly, however, is correct. Common "weather protection paints" claim a durability of the coating of 10 years.

I thought that wood had to be painted regularly or annually

If that were the case, there would be no ancient wooden barns. Painting annually would bother me as well. If you use larch, you can simply skip painting. It lasts a lifetime and grays over time. Only the end grain should not be exposed to the weather. However, it is also somewhat more expensive than other cheaper softwoods with paint.

Are metal houses very loud in the rain?

How about metal, are they really that loud in the rain?

I don’t find metal houses too loud in the rain; ours are close to the houses, partly with bedroom windows facing that direction, and the noise level is really okay for us and the neighbors.
Tip: when it rains, go to the hardware store/garden center and listen, that’s how we did it before buying.

Regarding selection: there are offers online in all price ranges/sizes.

Take wood and a good paint. For example, Jotun. Then it will look good for 10 to 15 years and you don't have to paint. Wood has many advantages. It insulates very well in winter, you can easily screw in interior fittings, is flexibly adaptable and above all very stable.

how about metal, is it really that loud in the rain? i thought you have to regularly or annually paint wood

nonsense. That's what hardware stores like to say to sell oil and so on