How can we make it happen? 

They either don't have the experience to understand there are other costs than simply PITI or they are making a decision too quick to stop and think about it.The reality is turnkey rarely works if you want to make sure the property is generating cash flow.

I’m looking to invest but want to the numbers so it make sense for the seller as well. 

No one to refer, but when considering a blanket loan make sure to understand the how the loan would treat removing collateral from the pool.

Yes, you can; this strategy is called pooling and it also adds a tremendous tax advantage You'll just need to make sure the entity pulling and disbursing the capital is structured correctly for its maximum benefit  

At the early stages, the more control you have over your real estate, the better returns thus I recommend investing locally to make your dollar go that much farther and gain a good familarity with real estate before exploring out of state investing.

Are legacy Homes priced lower or is it just the financing making them a good deal. 

Then I can make a decision based on the options in front of me.  

So yes I think this is a good deal, not sure how many partners you have on this deal but I think your decision depends on how much each of you need to make on the deal for it to make sense and how quickly you all want the return. 

I have experience with both and can definitely say that cashflow is nice in the beginning because it gives you freedom, but appreciation is what makes you wealthy.