From what I understand, you will only be able to attain REPS with your second W-2 only when you’re able to ensure that more than half of your total working hours are dedicated to real estate activities and exceed 750 hours per year.

What if I am a part-time agent to qualify for the REP status via mainly RE agent activities (helping others in buying/selling houses) and then also have a couple of investment properties on the side that I manage myself to attain passive loss from those properties (via depreciation)? 

Multifamily is 1 goal i will attain, 3+.

This is attainable and affordable.

Engineering is also hard by nature and once you've dove into the world of engineering, other things in the world seem more attainable. 

However, to reiterate what others said, I think you should decide on what your long term plans are and figure out what strategy works best to help you attain those goals.

I generally agree that if interest rates were the same between HELOC and mortgage, it makes sense to attain the flexibility to hasten pay off with ones extra cash flow - or borrow it back as desired/required.As for your last sentence, it's not "the same thing", simply because: interest rates are not the same!

Look where he is now.The story seems to be the consistent with many people that attain financial success.

Going into a bank and getting a loan feels the most attainable to me.

My outlook is that I want to replace my current income as much as possible, so that money (in the 401K) is doing nothing for me in attaining that goal.