There is 3-5% down payment options you can use.

I assumed you'd use HELOC for down payment + another loan for the rest. that is 100% financed. 

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I have equity in my CO rental; I don’t have a large enough sum saved up for a down payment yet so I’m wondering if a HELOC would be an option on my CO property. 

.- get into real estate with a lower rate and lesser percentage down payment.

If you have a good FICO, a decent down payment and closing costs, go ahead an do the first one. 

A lot of them contain Balloon Payment Provisions. 

I don't trust them and it so much more reliable to take a few minutes and look at your real competition to set pricing. 

I will be into it about $9,371 with closing and have a payment PITI including HOA of $1,205.

Financing contingency is there if you can't get the loan at the amount you thought, interest rate is raised or your payment changed higher than you put in the loan could give you an out.