@Ethan G.I have removed 30yr old water heaters that were still working fine, but as a rule of thumb, we replace anything older than 10 - 12yrs.    

You may be drawing in some of what happening by not following rules.

Are there any rules of thumb for this, or better yet - how would you deal with it?

@Marco Santarelli thank you for the informative reply, my forward thinking is on how to invest after say 4 acquisitions since I know the rules start changing in the financing department.

This is why disclosure requirements at first point of contact is required to be fair to the general public.You need to go buy the license laws of your state on what is dictated for advertising rules.

At the time I had a friend who for the purpose of not releasing her identity we will call her Stephanie.

The accounting rules in Malaysia are likely to be very different than the US because the taxation is VASTLY different.The OP needs an accountant that knows and understands Malaysian accounting and taxation rules.

Using the 50% rule, $1100 a month goes to paying expenses.

Also, I read about the 2% rule and I cant find a way to apply it in the South Florida market.

Hard money rates are regional and there are no rules each lender has their own way of doing business.