I have zero stress having the systems in place with the proper people in place to manage my day to day operations.

It's relatively easy to install and maintain. 

Take ownership of your mistake and learn to do the proper due diligence recommended above😊 

It's definitely worth investigating.Yes, you can install motion-sensor cameras to monitor vacant rentals, but they require some paid service to monitor remotely (wifi, hotspot, etc.) 

Some insurance companies are asking to see the home inspection report in order to give you insurance or to install a $750 water shutoff valve if the home is older than 20 years old.  

:Class A Properties:Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Vacancy Est: Historically 10%, 5% the more recent norm.Tenant Pool: Majority will have FICO scores of 680+ (roughly 5% probability of default), zero evictions in last 7 years.Class B Properties:Cashflow vs Appreciation: Typically, decent amount of relative rent & value appreciation.Vacancy Est: Historically 10%, 5% should be applied only if proper research done to support.Tenant Pool: Majority will have FICO scores of 620-680 (around 10% probability of default), some blemishes, but should have no evictions in last 5 yearsClass C Properties:Cashflow vs Appreciation: Typically, high cashflow and at the lower end of relative rent & value appreciation.

.), please describe for me the worst-case scenario for an eviction process if the tenant refuses to leave at the end of a lease term (assuming I do everything properly according to MA laws)?

It has to be handled in the proper way.

Several things to consider: 1) One of the main purposes of segmenting your assets into separate LLC's is so that your personal net worth or equity in other business ventures or properties isn't exposed, so unless you have a high net worth or a lot of equity in a property, it might not be worth bothering going the separate LLC route, especially when it restricts your financing of the property.  2) Most any commercial financing you get from a local bank for a small property is going to have recourse anyhow and require that you sign a personal guarantee, so you're still personally on the hook to the bank even in the case of a commercial loan.  3) If you're a newer investor and buying a deal that's tight on cash flow, or if you don't have a ton of cash sitting in the bank already, your greatest risk factor as an investor is your investment failing economically due to poor financing terms or not operating the investment properly, not because you get sued. 

There's no right or wrong way to do this, just varying levels of risk and the only proper route is the one you understand.