New here so I apologize in advance for this novice question. I reside in WA State in a small waterfront community called Hansville. Purchased the home in 2018 and it was built in 76. The home is a rambler (2000SF) and sits on 2 level lots. Purchased for 458k now worth about 750k.

Because of the age of the home it's in dire need of a remodel. In addition, I have so much unused and underutilized space in the form of a 3 attached garages. I'd like your honest feedback on a few scenarios I'm pondering. In addition, I'd welcome your experienced input if you would do something different than what I'm thinking. 

Scenario #1. Get a Heloc to remodel the dated home and convert the 3 car garage into an apartment to earn extra income/pay down the heloc. Fairly confident I could get between $2200-$2600 a month as a long term rental. 

Scenario #2. Get a Heloc to convert only the 3 car garage into an apartment for traveling nurses?

Scenario #3. Get a Heloc to convert only the 3 car garage into an apartment for AIR BNB ? 

Scenario #4.  Do no remodel to the primary house or 3 car garage: get a Heloc to build a detached garage which would include an apartment upstairs for either short term or long term tenants? (There is enough room indeed for this) 

Scenario #5. Get a Heloc and do some form of a remodel and also use some of the proceeds for an investment property. 

Scenario #6. Do nothing to the primary residence and use the HELOC to assist in purchasing one or 2 investment properties?

You can also view my property on Zillow: 37966 Fawn RD NE. Hansville WA. You'll get a good sense of how "long" the property is and the pictures of the garages. Photos 14 thru 18 show the 3 car garage extra storage room and garden room. 

I'm not interested in selling by the way so please no solicitors.

I'm genuinely interested in comments based on your experience. The pros and the cons. 

Thanks in advance for any information you can share.