Many banks securitize their loans (bundle them together) and sell the loans to Fannie Mae or Freddie Mac, while continuing to service the loans, that is collect your payment.

These properties can provide cash flow and diversification while qualifying for favorable residential loans.

Unless it’s specified by your loan type or lender, you don’t have to.

Also, did you have any other loans (ie student loans, primary residence mortgage, etc) when you took on the $25k? 

People reinstate the loans and do loan modifications all the time.

HELOCs are not available because they are residential loans guaranteed by individuals and what you seek is a type of commercial loan or credit line which are available to seasoned companies with proven financial track record.

I initially got a variable loan.

Cash out refi only if the rental income significantly exceeds the monthly payment and you want liquidity to invest elsewhere.2.You can maybe do a HELOC if you want a smaller loan that doesn’t involve refinancing the entire house.3.

You could use a HELOC, but with VA loans you have an allotment so you can get loans on more than one home depending on how much bandwidth they give you.

Your loan would be on a different property so no financing on the property you are buying.