With the relative stability of real estate (in certain markets) and rental income providing double to triple what treasuries pay, I can see real estate taking an increasing weight in portfolios to fill the void.  

Maybe (most likely) even triple.

Certainly not overnight, but those who were able to buy upwards of $500k-$1,000,000+ worth of property in Southern Cali, Vegas, Denver, etc. back in 2010, probably saw their net worth double or triple in the following 9 years.I consider $1mm as 'wealthy' so that's my metric for this exercise. 

Like baseball players settle for a run now and then and then once in a while will hit a triple header or a home run.We all have a time factor to play with and if you just become consistent about earning money you can keep going until you hit that really profitable deal.

3)What's the pro/con of duplex,triple, and  quadplex?

Failure to provide this, or withholding for incorrect reasons can result in triple damages, at least in some locations.

if not i could just have my parents buy the property i want and have them sign it over to me.also, like i said earlier phoenix recently experienced a huge boom, preperties tripled in value in about a year and a half to two years, they peaked, and over the past year and a half have been slowly coming down but they arent as low as they were before the boom.

. - these items would likley triple the required reno budget.

Also, if the triple-decker idea is not great, does anyone a better idea for a first property for a buy and hold investor?

I doubt SC would be triple or more.