I recommend excluding any city on this list because they are unlikely to get new jobs or grow in population.Appreciation - Unless properties consistently appreciate at or above the rate of inflation, your actual income is declining over time.

I started encouraging the aspects of real estate she liked...

This is different than capex and consists of smaller, less costly items.

My CAP rates were in the mid to high teens, with consistent bank statements to prove it, as well as long term tenants, and no capital expenses needed.

I really like the idea of investing into index funds, but am now liking the hands on aspect of real estate.

The only time I've consistently seen banks willing to go IO, especially in "weird" markets like right now, is when there is capital improvement in the plan. 

The property consists of a desirable unit mix of one one-bedroom, one-bathroom unit, seven two-bedroom,one-and-a-half bathroom units, and two three-bedroom, two-bathroom units.

I am thinking about starting with multifamily homes in the Lowell area, because the prices there are lower than they are closer to Boston, and then possibly investing closer to Boston once I have a few properties generating income.As I have said most of my research has consisted of videos and podcasts.

If the management company is excellent at their craft and they attract and retain top talent in related services (like contractors and agents, since there is a lot of overlap between PM and these fields), then the agents and contractors may be far better than the average agent in that same metro.Conversely, if that PM company is not led by a skilled business tactician they might be tempted to retain a shiza agent in their ranks so that they can capture some referral booty, with no mind to whether or not the end user client is getting good representation.I see both things happen in my market consistently, and though it doesn't create a helpful rule of thumb, hopefully it does help you in your decisions ahead.

However, as with most aspects of life, fear and uncertainty can almost always  be reduced or eliminated through education and familiarity.