That would free up your cash quicker and allow you to build a portfolio much faster.

I have a rental that is almost paid off so I can refinance it or take a Heloc , whichever is quicker or better ...

By the way, a mentor is a great way to skip the learning curve and get to results a much quicker than not having someone to point the way and to tell you what pitfalls to avoid.

Another reason I like them is the better possibility of getting a Property Management Company on a 30 unit project that keeps you away from the daily maintenance, the Tenant screening,  and their ability to get people to make repairs and get them done quicker and handle anything that comes up. 

You never know if you don’t ask.Also consider moving somewhere cheaper or a roommate situation so that you can save up for a down payment quicker.

It helps me get it rented quicker by adding value.  

Flips seem to make the most sense for quicker income and cash generation and can turn into a rental if they don't sell quick enough, I know multi family can be great for longer term wealth creation though...

I would go with a 10 or 15 year fixed rate mortgage so that I can build up equity in the property quicker.

I heard of many who have  paid down big chunks of their principle at a time, putting their paychecks into the HELOC and then repeating the process for a quicker pay down of the mortgage principle, but not one that pays it all off and takes over as a 1st lien position without having enough equity to begin with.

He may also make accelerated payments to pay off the principal quicker (in 10-15 years).