I can buy a piece of gum for 50 cents and hope to turn around and sell it for $100.  

Usually these homes have been worked on by folks that shouldn't be allowed to own any tools and are held together by duct tape and bubble gum.

Nope, but I did enter into a contract with a self identified flipper who was a scummy, sleazy, lying whole seller who could not buy a pack of gum with his own money... 

I promise you that you can walk and chew gum at the same time.

Candy bars, pack of gum and the daily newspaper used to be $0.05.

Would like some advice on ways to find best deals on Buying rentals in Shirley, Mastic, Mastic beach area.I have seen most deals are taking already before they even hit the market or are listed and seem to have buyer in place already.  

I have never heard of Ductwork having to be replaced the system having to be replaced, yes. if the existing Ductwork leaks then look into sealing the joints with duct mastic ( do not use the grey duct tape) or us the silver duct tape. if the ducts are in the attic and bare metal try getting some duct insulation and wrapping them - just a couple of easy solutions.

I have heard horror stories that 100+ year old properties are like gum on the bottom of your shoe that never goes away.

Now I could of ran off and bought 25K worth of Bazooka Joe bubble gum.

Only problem is that the tile was laid over black mastic which contains asbestos.