It all depends on what your goals are. 

Like Ken said, really depends on what you're planning on doing with the property.

Not all houses make good rentals and depending on how well the people who bought them ran the numbers, will determine how well they cash flowed (and some areas that is not possible at all).

Typical rates are 8-12% of income either monthly or yearly depending on manager.

As usual, the answer is, "It depends"...First, what are your goals? 

Consider how you'll reinvest rental income, save for future down payments, and scale your real estate portfolio over time.Ultimately, the decision to invest in real estate or continue with your index fund investment depends on your individual circumstances, goals, and risk tolerance.

The cost is likely dependent on the level of customization and depth needed. 

Private Lending Attorney Here-First it depends if the person lending the money will be doing this on an ongoing basis - if so he may want to have a separate entity created for that business.As far as documenting the loan - I would recommend speaking with an attorney who regularly handles these transactions. 

No right or wrong answer, it depends on how savvy are you at renovating, how long do you anticipate on house hacking?

It will all depend!