That makes you (or rather the tax return that reports it) the taxpayer.If you are contemplating taking title to your new property as a single member LLC that will be taxed as a sole proprietor then you might be able to. 

I am seriously contemplating throwing some 1/2 drywall over it even though the handyman already did some removal of all the lose stuff.

If multiple lenders refuse to lend to you then perhaps contemplate the remote idea that perhaps the issue, if there is an issue, is not at the lenders end.Lenders have sweet spots for where they like to lend.

Someone please let me know if what I am contemplating sounds really stupid?

I have been contemplating on purchasing a home in this area but most of the homes are old and needs some TLC.

I am contemplating buying a co-op with my longterm girlfriend with whom I have a child.

Spec homes are much easier, quicker and more profitable as what you are contemplating is basically a custom build process.All that being said there are some really successful strategies you can employ to ramp up the process and accomplish your goals. 

I have a friend with $4M in a savings account who has been contemplating a rental investment for the last several years, and he still is as of today :) Once you buy a property from an agent, you will notice that they are willing to spend more time on you

Currently, contemplating about possibly converting our 2 car garage into an ADU to create cash flow.

We are contemplating either adding them to the deed (and incurring those closing costs) or separately entering into a joint venture agreement  whereby they will gain a contractual right to 50% of the profits from the project in exchange for paying 50% of the costs, etc.