E.g. faucet repair, light bulb, HVAC filter. 

“Construct” and “rehabilitate” mean only work done on-site to the structure, utility connections and landscaping."

If the returns are looking better then that, then as Walter White said, "then maybe your best course would be to tread lightly." :)

@Wei Cho is an expert in this and perhaps could shed some light on the first question.With regards to the market value it depends because the appraiser has to substantiate the value add as determined by comps that have recently sold with visable ADU's as well.

It seems the NYC real estate landscape is heavily regulated so flipping and assigning contracts (especially in such a competitive and well-priced market) would be an uphill battle...

Doing some light research it looked like the TK properties I could afford with my current cash and conventional funding would only cash flow a few hundred dollars a month while consuming all my cash and purchasing power.

I always replace faucets, lighting and anything else that would cause a tenant to call in a maintenance request.

Can someone please shed some light on it.

I made $15-20K a summer mowing and landscaping throughout college.

Or, is the basement already finished and you truly aren't changing any features, e.g. walls, lighting, etc?