Passive income generation and retirement ?

[Tim Crumley]

I am a former home builder (thanks 2007- 2008) married to an active real estate agent.  My wife only sells new homes.  During the down turn I took a job with a large insurance company as a large loss (fire, tornado, hurricane, etc) residential property adjuster.  I am always travelling and that is getting pretty tiring.  The job is nice and pays well but I am an entrepreneur at heart.

 We have been discussing getting back into the real estate game as investors this go-round but I am still a little gun shy about getting too leveraged. We have already lost EVERYTHING once.  We did retain our credit for what that's worth.  

I am interested in generating a passive income to carry us into our old age.  I was thinking that a $100k/yr income would be sufficient to allow for spending and saving.  Based on what I am reading it seems that to generate a personal income of $100k we would need to be bringing in near $200k in rent.  At a rent of $1000/month (way outside the range of mobile homes that I was originally considering) we would need 200 properties.  That seems crazy.  There must be something I'm not thinking about. 

This passive income is a future goal and I understand that it will take many years to achieve. I have no immediate plans of leaving my job but would like to perhaps change jobs in the next few years to something that will keep me home a little more and allow more focus on REI. In order to do that I will need to generate a secondary income to off set the likely pay decrease. Who knows what will happen by then though, maybe we find that we have a knack for REI and go full time. It seems that flipping would have to come into play then just to generate a decent yearly income.

Any advice or insight would be appreciated.  

Sorry for the long first post.