How quick you can scale will depend on your future work income as well as rent and equity appreciation in the property, but either way this is a good start. 

I think renters with disbilites are good for two reasons. 1. they have a consistant stream of income and 2. depending on the disability they are more likely to stay longer in your rental.

We see on average 5-7% of monthly rents going back into general repairs and about the same to capex depending on the property condition.

It will depend on your demographic @Ethan Swat. 

As far as whether to rent or buy, it depends on your personal situation, though as it's a new area it may be a good idea to rent for the first year while you decide where you'd eventually like to purchase.

This is really dependent on the stage of your investment life.At your age starting out I would be heavier into cash and 401k.  

It all depends on what your goals are. 

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

Depending on the location, the home could benefit from appreciation in value and/or experience rent growth.

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).