Also, for flips, I like to reserve an additional 15-20% in contingency for unforeseen conditions or changes. 

That process has direct lender involvement.Where the challenge lies, is when unsophisticated "investors" with no experience, no money and no reserves use creative financing (often called wrap, subto, lease option, seller financing, land contract) to purchase properties and along the way there is a "hiccup".

Retain a cash reserve to cover vacancies or downturns, and align with your long-term goals by consulting a financial advisor.

You know, it only takes a phone call to reserve a large meeting room, holds about 250, if you clean up after yourself, it's totally free in a new facility, it called the Library.So long as there are no sales, no charges, not some income producing ploy at your meeting, you can use it. 

I keep a very healthy amount of reserves to avoid using my insurance unless I have a catastrophic issue.

With that being said, what you described sounds like Owner Contribution (initial reserves / deposits by the investor).  

2) How long can your reserves support the negative cashflow3) What's your plan to solve negative cashflow long-term?

Best tips are take it slow and make sure you have significant reserves when you leave your w2 also don't buy a company car if you already have a car just to say it's for work.

But balance is key—keeping some cash reserves for unexpected expenses is critical.Lastly, I’d recommend running detailed numbers to ensure the property cash flows well, even with conservative estimates.

Make sure to include reserves for long term vacancy and maintenance expenses. 3.