Due diligence mitigates most of that, but things can and do still happen. 

So say I waive all contingencies on my offer EXCEPT home inspection, but then I have an issue with something I waived, for example:I waive the radon contingency, I do the radon inspection anyway and it comes out that there is radon to be mitigated.

A reverse exchange can help mitigate this but a willing buyer like you're looking for who will give you some lee way on the closing dates will server you even better.Sounds like these are student housing and are prime candidates for a portfolio sale to one investor. 

Now you are over leveraged because you only got 1k a month net but your note is 1600.How to mitigate over leverage?

I'm aware there are risks involved, but they can be mitigated/minimized, and the reward is definitely there. 

They are also mitigating their risk of a weak buyer (who has limited down payment and likely limited reserves) by setting up a balloon.

Would love to hear how others manage and mitigate this very frustrating issue!

I am prepared to potential deal with a long distance purchase situation, even though I understand that may add some complications/risk that will need to be mitigated as best as possible.

The best time to mitigate your risk is during a stringent screening!

For most people starting out, a lot of the scaryness can be mitigated by continuing to read, listen to podcasts, and meet people.