Are you leaning toward a specific strategy like buy-and-holds, flips, or house hacking?

And your net worth will thank you.If you still want to go ahead, you'd be better off buying a house than an apartment because, while the value of the building itself will go to 0, you'll still have the value of the land, bearing in mind that the land might actually lose value too given the depopulation and the yen depreciation.Sorry if I'm pooping a party but make sure you understand what you're getting into (which you're already doing by asking the forum) and then make the decision that's right for you according to your objectives.

Buying a large new build home can also work well as a house hack as you can charge a premium rent, and generally most bedrooms built now a days have en suites (at least in my market).  

I warn people over and over and over to know what they are buying and to go personally see what they are buying. 

Don’t forget practical items like toiletries, a cozy blanket, and a handwritten welcome note.To balance cost and quality, consider buying in bulk or looking for local products that offer great value.

You are 18, you shouldn't be ready to buy a property yet.

2. how to know where to find a B,C,D areas\neighborhoods in cities\ countries.3. how do I know if a property is worth the checking\ buying?

If you want to manage your own properties, I would highly recommend buying within an hour of your primary.

John Hickey congrats on buying a cash cow.

Quote from @Luis Herna: Let say I am a licensed real estate agent in oklahoma and there is one buyer in new York wanting to buy a property in Texas.