2)Should I & him jointly own it 50/503)Should I set up an LLC (NOT trust) that owns the house & we both are partners in LLC?

Within the individual "child" series you can establish an Operating Agreement that will reflect the ownership appropriately.I wrote an article some time with more information on how to effectively conduct a joint venture.Hope this helps!

Your capex is pretty healthy and conservative.  

Nothing was vented and most joints had burst from freezing. 

But if you each own 50% TIC and the property you are selling is worth $175K you could sell it and purchase the 50% of your partner and still do a full exchange.The other issue you'll have may be the mortgage on the jointly held property. 

The most commonly implemented solar tax credit (Section 25D) for residential, primary residence, is simple enough to understand.However, for us 'flippers', it's much less clear, unless you decide to house-hack and live in the property as a primary residence.The IRS still provides a healthy 30% tax credit for implementation of solar, but it's much more convoluted in Section 48 (commercial credit). 

You can pay the amount owed to the general contractor but issue a joint check to ensure the check is paid to the party who issued the lien. 

Company claims this is normal and feel joint filler is the answer. 

Keeping a healthy 6-12 month of expenses banked for each property is an important factor.  

During a prep for deployment I started to have some issues with the function of my hands and other joints, and eventually was diagnosed with autoimmune arthritis.