Your accountant is probably correct from a bird's eye view.Premiums are generally non-deductible if the beneficiary is financially interested in the insured, and the insured benefits either directly or indirectly from the policy, even if they would otherwise be deductible trade or business expenses under IRC Sec 162 or expenses for the production of income under Sec 212.

Therefore whenever you are considering an investment you need to make sure that such transaction is an "arms length", meaning that these persons can't be involved directly or indirectly.

If the basement is not reno'd. etc.In my research and learnings (courses, videos, etc) I have never seen anyone factor in HST on their calculations when looking at a property.Would be great to get input from both renovators and investors on this.One site/article that I thought was quite detailed is https://www.bakertilly.ca/en/btc/publications/indirect-taxalert-are-sales-and-renovations-of-used-residential-house. 

In addition to that you must understand a "prohibited transaction" rules as defined by the IRS:https://www.irs.gov/retirement...Basically your retirement plan can not engage in any transaction, directly or indirectly with "disqualified person". 

It's the fastest way of losing money- Investing in direct REI at least you know you will not losing principal- For OOS, result is hit or miss, but for long term you will not lose the princial although you may not hitting the advertised target.

An added reason, not the main one, is that there are plans to build a railroad that would connect This town indirectly to Philadelphia (If built it will be within the next 6 years ).

Perhaps, in the very distant future but San Antonio is still in TX, a state with very landlord-friendly laws, which indirectly affects rent growth, so I'm not quite sure it is an apples-to-apples comparison unless I'm not following your point.

Or indirectly from the increase of profit from there busyness from the price increases or increase in there asset prices which they can sell or borrow against to increase their purchasing power.

Especially this may just show up as an increased tax but this is indirectly a lien on the property for an improvement that they have done.

Keep in mind that if you don't book anything through Airbnb and are successful in directing all to book directly, you will actually not get to be Super Host and will lose search positioning on Airbnb.