I would suggest a few things: 1. don't make repetitive log entries every day " managed rental, did calls" copied and pasted 50 times likely would be thrown out in an audit for example. 2. make sure you are materially participating in your rental activities. 750 hours is not enough, you need to pass the second test of material participation in the rental activities to turn that activity from passive to active and claim the deductions on your active income. 

However if you plan on buying 3-4units, there is a trigger rule for FHA, it is called the self sufficiency test.

Child tested very low but lead did not come from housing.

San Francisco just passed law that anyone receive City assistance must take a drug test and the cops can now go after the smash and grab thieves.

It is highly recommended that you get a radon test before buying or selling a home! 

I’m torn between selling it and finding an apartment/whole building in Tokyo or doing some light renovations and testing the rental market with the older house.

Stock indices have withheld the test of time, that's where I've placed my savings as I wait to gather enough knowledge/cash to invest in a property. 

Test their knowledge against what you have learned.

You can have someone bring in an adequate generator to test whatever you feel the need to test.

Because you're essentially taking on the duties of a General Contractor without knowing what you're doing, or having passed the tests, or paid the money.