Local credit unions or banks where you have other accounts may give you better rates.Commercial financing is a little harder to find, but there are still tons of banks that do them.

Look at credit unions and find their investment property rates. 

I was turned down for a HELOC with a different lender (a local credit union who would've given me more credit, but determined my current debt-to-income is too high, especially since the rental property isn't generating rent at the moment).I know that I can do a cash-out refi on the rental property in a couple months.

Or a community bank or credit union should be able to help or point you in the right direction.

I'm currently on the lookout for local banks or credit unions that specialize in offering portfolio or bundle loans for investment properties.

I called my local banks as well some credit unions but they unfortunately only offer for primary and secondary homes. 

For smaller loans like that, regional banks and credit unions are often the best fit.

Are you getting quoted with a Credit Union or Bank?

I had checked with most of my local banks, big banks, and credit unions and they seem to all say that they only offer HELOC to primary residents.

I had 8k saved up, a 10k approval for an unsecured loan from my credit union, decent credit to get a Home Depot card, maybe a few grand to borrow from a 401k, and it was warzone shopping time.