What if I am not only looking to do quantitative analysis but want to consider some factors that are more qualitative?

Easiest way to look at this generically would be:Proposed mortgage payments + any other monthly payment you haveYour monthly income + 75%*long-term rentsThis always needs to be less than 50%, and of course other factors would influence your ability to qualify but this hopefully will give you a way to guesstimate the feasibility. 

However they haven't had any other offers and it has been on the market for roughly 70 days.At the accepted offer rate our mortgage would estimated be:Year 1 - $5231Year 2 - $5750Year 3-30 - $6292Each of the 3 units would rent for an estimated 2-2.5k totaling roughly 6k-7500 per month in income depending on what we can rent each unit for.So with all that being said, conservative numbers the triplex would cashflow roughly 1k per month assuming we don't live in it and have all 3 Units rented.That seems like razor thin margins, especially when factoring in expenses so my question is:What is the cash on cash net return per month you would look for in a triplex deal like this?

That's unique factor to U.S.. 

So, check into that as that may be an additional hard cost you need to factor in.

This is a loaded question and there are so many factors to consider when getting started.

In addition many of the decorations will be Interactive to increase the fun factor.

This factor can significantly impact your cash flow potential, especially if you're contemplating a buy-and-hold strategy.

The unknown is a big factor that WILL cost you money in the long run.

It is imperative to evaluate the timeline for recuperating the substantial capital investment, especially if your goal is to expand your rental portfolio efficiently.While cash flow is undoubtedly significant, it should not overshadow other crucial factors in real estate investment.