This translates into lower gross revenue and kicks off a downward spiral that is tough to stop without an injection of cash equity.

There's no major "wealthy" cities nearby to inject money into the town as a vacation destination. 

If so, it will depend on how you injected it in the first place.  

@Tim Vecchioni, yes, I know, YOUR cash-on-cash return after 10-15 years will be much greater than 5.5%/y, because of your small percentage of cash injection in the first place.

Just add up all the cash you put into a property (purchase plus any other cash injections such as repairs) and compare it to all the cash you got out (cash flow plus net sale proceeds). 

I think that factors such as short supply/ high demand, low interest rates, and asset price inflation due to the massive injection of liquidity into the capital markets will all keep property values elevated for the foreseeable future.

It seems to me that a phone call to the intermediary getting them to talk to the tax prep person would be a logical first step vs posting the question to the forum and trying to inject yourself between two experts.Just my 2 cents.

Please advise what type of agreement typically is signed when a passive investor is injecting capital for a real estate project: Real Estate Capital Agreement, Real Estate Investment Contract, etc.

Now I need some advice I am able to inject 15 k$ now from my own money to keep things running and I may be able to get around 120 k$ in may for a new investment.

You will learn to look at things 2 or 3 different ways here as sometimes we say things we dont mean but there is no way to inject a sarcastic tone into the printed word.It is a good practice to always look for another meaning in a post (other than the obvious).