Renting Apartments: Ceilings and Walls

Ok so this is a triple question.
I rent a 1DK mansion and its my first time with this size of apartment.

1.) I am considering investing in a loft-style bed. I am concerned about the height of the ceiling and I am wondering if this type of bed needs a room with a high type of ceiling. (I dont want to hurt my head waking up) the question is does anyone know if there is an average height of mansion ceilings?

2.) The second question is the walls, I did/am doing some research on this but what are the alternatives to hanging things like posters without damaging the walls? I found a product that is like putty that you knead and then tack it on the wall.

3) My balcony will have stuff on it, what are some good things I can protect it from storms and such? Like a tarp?

「 I am considering investing in a loft-style bed. I am concerned about the height of the ceiling and I am wondering if this type of bed needs a room with a high type of ceiling. 」

Like, does a bed that's twice as tall as a normal bed work best in a room with a high ceiling? Yeah, definitely. There's not a universal height of apartment ceilings in Japan, either, so I'd recommend asking your landlord how high the ceiling in your apartment is.

If you don't have a landlord yet, because you don't have an apartment yet, I'd advice holding off on buyin furniture until you've finalized where you're going to live.

I agree with the previous post.
You need to check the size of the room including ceiling height before you by because there can be a difference between the departments.

For hanging things on the wall, it is recommended to prevent hanging.
Stickers or other ways can only damage the wall paper or discolor the wallpaper.
Normally with rental departments you need to hand it back the same way you have received it.

For changes you better to discus with you landlord.
There are many different rules depending from who you rent.

I agree with the above posters. You’d want to wait until you see and select the exact property you are going to rent. “1DK” can be extremely small or comfortably big, the building construction would vary from one to another.

Posters: I’ve used small pushpins before.

What kind of “stuff”? People might put their washing machines on the balcony, maybe plant pots and buckets and things, but you’d want to check the balcony too before you decide to put things outside.

Just try to get a place first. It is very difficult to find a place as a foreigner, and the whole process can take several months and multiple rejections.
Also be prepared to pay a lot extra in upfront as foreigner, not sure which city but in Tokyo you can expect to pay 1-2M yen upfront for 1LDK.

but in Tokyo you can expect to pay 1-2M yen upfront for 1LDK
If you rent an expensive apartment maybe, but that is unrealistic. Real estate agent fee, key money, landlord "gift" and bond might add up to six months rent which can be a lot less than that - depends where yoyu live and what your budget is. Some rental companies don't require that (I had a contract fee of 50,000 yen and that was it.) Last time I looked at an apartment closer to the central city it would have been 300,000 yen upfront.

As for ceiling height - find an apartment first. I've been in places where some parts of the ceiling were very tall, but other parts it was actually an angled wall. Basically sleeping in a normal bed you'd have to be careful due to a very low ceiling.

1.) Have you thought about renting a room with a small loft instead of buying a bed? A room with a loft is popular among single men, because you can sleep on the loft, keep it messy, and still have friends over. Here are examples:
https://www.google.com/search?q=%E3%83%AD%E3%83%95%E3%83%88%E4%BB%98%E...

2.) Discuss with your real estate agency, landlord and your local "home center".

3) Go to a "home center" or stores like Tokyu Hands and look for 防災グッズ (bousai goods: Disaster prevention goods) to protect your things from storms and earthquakes. It's important to be aware of natural disaster, because you will eventually protecting your neighbors from being damaged by things that fly away from your home. Additionally, depending on the balcony, you can't put many things on it for fire and disaster prevention reasons.