Have it written in to your lease, which should be month-to-month, so if they violate it for something other than non-payment you can easily part ways and disentangle them from your life.

If so did u find new tenants easily and did the old tenants leave peacefully?

Within 10 years you can easily earn $500,000 or more.What happens if you sell?

if your lease clearly states "no smoking allowed on the property" then that's pretty cut and dry and you can more easily enforce that. 

You could easily make several videos about each of those 

thinking if it is right option to get heloc on my primary residence which I think I can easily get 150K out of it.

After two years of appreciation we would easily be in the black.

One can get lost in the minutiae really easily.

The property I'm referring to has been meticulously maintained, no mortgage, owner was wealthy and recently passed away in his 80's and now the kids are in charge of selling and want to maximize the sales price on the MLS so it's not a one on one negotiation.It's a 16 unit with average rents at $400/month and market rate is $800-$895.Let's assume all cash purchase so mortgage payment isn't a factor and use 50% rule for simplicity:$400×16×12 = $76,800 gross rents50% rule NOI = $38,400At $1,000,000 asking price the cap rate would be 3.8%If you can easily increase rents to market at $850/unit:$850×16×12 = $163,200 gross rents50% rule NOI = $81,600At $1,000,000 asking price the cap rate would be 8.2%If comps are selling at a 7% cap rate the sales price of this property could sell anywhere between $548,571 using actual NOI and $1,165,714 using market rate NOI.Clearly you shouldn't pay $1,165,714 based on unrealized potential, but it's also clear that the sellers would not entertain $548,571.

I made the qualification  4x rent because the utilities for the house usually run $280/mo to $400/mo and I thought that if a household only makes $2250/mo (3x rent) in gross income, then their rent plus utilities could easily be more than 50% of their net income.