You're dealing with your "bad apple" that will forever help you curate your search criteria whenever you place future tenants. 

I'd focus on deciding what you want to do (flip-high risk, but potentially high return...or large loss; short term rental-more work, but higher return than long term rental; long term rental-less work than the other two, but lower return).Once you've decided which you want to do, then focus on getting the best house to meet your goal. 

I use the one time number to order and then it can not be used again in the future.

One time I had a guest smoke and it went right up the ducts into my unit, it was awful.I'm conscious about how that could potentially affect guests who will be staying in the upper unit in the future.

I was reading up about it, and saw that the cons of oil heating include needing to top up the oil supply, lower efficiency (than gas and electric), and potential leaking of tanks leading to environmental issues.Is anyone familiar with oil heated homes?

I hope things go better for you in the future. 

Thank you @Jaycee Greene and @Hossein DaneshIn sum:- 42 apartment rental deal (land has potential to add 32 more on  two small building but that phase would be out of scope for this initial stage analysis).- Negotiated sales price $3.2 (seller financed)- 30% DP @ 7% / 20rs.

Investing out of state in the KCMO area sounds like a smart move; it’s such an interesting market with plenty of potential.

Letting someone out of the lease is not the same as nullifying that the lease ever occurred; it is just an agreement that you won't go after any additional months of future rents that would otherwise be owed.

And that's the very WORNG thought path too many have coming into such, they think it assures future returns.