At those price points, all major systems should be on the front end of its lifespan and really, the AC should be new and Roof less then 5 yrs old.  

Nothing wrong with a Good financed buyer, and they're likely the majority of your buyers.

But I don't see any major concerns with regards to the cash flow numbers you posted, unless there are hidden expenses (insurance, capex, deferred maintenance, management fees, etc).There is always a risk when inheriting multiple tenants. 

But how do I find out if there is a major problem that I am missing through ignorance?

Most lenders will require you own the property for 12 months before they will allow you to use the new value to pull out cash, before that most will only recognize your purchase price even if you have done major renovations.

You are in the upper part of the country, so you may want to market/list the property inmajor Canadian cities near your subject home (within Craigslist_if available, hospital community boards_ lunch rooms, major & prestigious Universities, and prestigious employer community bulletin boards.) 

This excludes servers, bartenders, etc where the majority of their money is made from tipping.  

I would definitely use a contractor to do the majority, if not all of the work. 

Hi Everyone, Thanks in advance for your advice/comments. 4-Plex for sale near a major university.

Earlier this year we bought two houses that needed major work.