I heard it cost $100 filing fee so I didn't want to waste money if I didn't have to. 

I got the duplex for a very good price so I financed more money than the cost of the house so I don't have to pay for the rehab out of pocket.

Her unit needs to be improved or I fear that the costs to fis it up will grow without decent maintenance.

Haven't had issues because the properties net enough to repay those costs and cashflow from year 1.

Passport 2. 2 Months Bank Statements showing downpayment + closing costs and reserves (typically 12 months) 3.

Can you do side hustles, cut down costs to get rid of these debts?

You are exactly correct that every project always has a wrinkle that costs more and takes more time. 

I guess it's just too many factors to consider and it easy to get overwhelmed and cannot get accurate info and estimation when I conduct analysis (ex. property tax rate, insurance, maintenance fee, rent, repair, closing cost, etc.) 

There is a cost to prepping the home for burning which includes removal of all hazards and permits.  

A good real estate accountant can save you thousands of dollars by leveraging entity selection and formation, tax deductions, cost segregations, bonus depreciation and tax planning.I recommend finding an accountant who specializes in real estate taxation, business taxation, financial planning and tax planning.You may want to consider working with your accountant remotely to expand your options.I would also recommend looking for a accountant willing to work with you throughout the year.