I have some experience with HELOCs, but usually for smaller amounts and I am wondering if I can take out more than $100k in cash from the HELOC. 

Your maximum allowable purchasing power is going to be entirely dependent upon your experience, liquidity, and leverage you can get - which will be deal specific and investor specific.

He is experience, but not in Detroit.

To grow your network and get insight from the experiences of others, go to local real estate meetups, networking events, and seminars.Seek out a mentor with knowledge of subject-to transactions and wholesaling.

In my experience, most private money lenders will very rarely lend money on a deal in which the deal maker does not put any money down.

Happy to share my experiences. 

@Tara AdiI am not an attorneyMy experience has been owning a condo as well as building 1,000’s of themIn this instance there was a defect from the common area element that caused damage to the window which would be the responsibility of the HOAThink of it another way, if the roof leaks and destroys your drywall ceiling - are you responsible to replace the drywall?

Would love to connect with people that have some experience in Commercial multi family and could guide me to the right direction.  

What made this opportunity particularly enticing was my prior experience managing this exact duplex for the same investor over a span of three years.The property itself is a 1950s duplex that underwent significant renovations in 2017.

The learning curve can be steep, but with dedication, education, and networking, you'll gain confidence and experience over time.