I also heard they had a loan on all of them that would not allow it.

Most (not all) HELOCs require that the property is titled to an individual (not LLC) and are full doc, meaning your employment history, income, DTI etc will be factors.

This would allow you to sell a property you had purchased with the intent of holding for productive investment use. 

We currently accept rent from tenants using a variety of 3rd party apps-Cashapp, Venmo, Zelle but are moving away from accepting payments in our individual names and want to start accepting payments directly to the LLC/business accounts, but LLC accounts do not accept Zelle and there is a fee for using business accounts on Venmo.

Happy to chat...being a local GC takes out a lot of the risk of the biggest variable for most investors (unpredictable rehab costs) and also allows you to consider more options than the average investor, with your rehab costs being significantly lower.

Living in one unit and renting out the others allows you to deduct 75% of expenses like mortgage interest, property taxes, insurance, and shared repairs as rental expenses, while the remaining 25% applies to personal use.

Though I would caution you on hard money lending until you understand the industry a bit better, that can be very rewarding but you have to be able to do your due diligence on deals because you're turning over your hard-earned money to an individuals project, often a flip. 

If your escrow company allowed that to happen, you should go after them.

I'm currently building up capital for future ventures and properties that I find on market, as well as attempting to find the best brokerage where I can work under an individual who is already more established.

The Purchase and Sale Agreement is the contract that you and the seller sign which allows you the option to purchase the property at the agreed upon price.