But, can definitely depend on your local market.With the market so strong for the sellers/landlords, what you see being advertised is what did NOT move. 

Some units bring in $700/month after expenses and others bring in $300 depending on the location.

How to respond depends on whether you want to keep him as a tenant.  

Hey @@Andrew Lee, if you go with a property manager, you can expect to pay 15-25% depending on the area.

A few notes on the questions you asked above:- My security deposit changes depending on the number of tenants and pets.

I think if you can get a good team, hopefully a good handyman, plumber, know of a good electrician and a good HVAC or furnace guy depending on where you live, and follow through with late fees and posting notices when someone goes past the late fee (you have to train your tenants or they will always take advantage of you) then you will be fine.

Depending on prices you’re looking at I would expect that you will put in/leave in some of your own money. 

It depends on many factors: employment, broader US economy, migration trends, city revitalization initiatives, economic diversity of the area, etc.

Depending on the locale, the Owner/Builder route will only work on your own home, not every project you come across.

In class C neighbours, depending on crime rate and some other factors.