I'm sure there's still the risk of getting sued even with commercial lending but I bet it's less than the residential side.

I have a strong passion for multi-family residential and commercial investing.Any ideas?

Residential liability risk is super low. 

I am a carpenter by trade and have 25 years of building experience in residential & commercial.

1-4 units is residential loans; 5+ units are commercial loans… these are significant differences.

My company has been doing residential Spec builds in Austin for the past 6 years or so and recently got into doing Custom builds, an architect we have worked with in the past approached us and basically he wants us to build a house he's already designed for his clients, (we are still in the process of meeting with them and doing estimates etc.), we verbally agreed on a 20% GC fee over construction costs, but I have a feeling he will want to split this 20% fee with us somehow as he tried to do something similar a few years ago in a project that didnt end up happening (he wanted to split the 20% in half between us) which we didnt think that agreement was fair at the time.

The other option was through their residential department where I could get a 30 year FIXED rate loan at 80% LTV.

In my experience, all investment properties are falling under the auspices of a commercial loan, and not residential. 

Looking for what your experience been with conversions of a multifamily residential (tenant occupied).

I am looking into investing in single family and multi-unit residential real estate.