[Wolffink]

I think that's the wrong way to look at it, to setup a certain limit on ETFs.

First you want to diversify. If you don't have any investments at all, then ETFs can take care of most, if not all, of your investment needs (perhaps you want to buy a house so there's that....).

Based off the Couch potatoes portfolio

ETF Inflation-linked Bonds
ETF Reits
ETF Overall US market
ETF International Market
ETF Emerging markets


I wouldnt buy into REITs right now though as real estate seems on a bubble.