In the case of my tenants they were foreign nationals who were not allowed to work in the US. 

Unfortunately it's much more difficult to obtain credit and criminal backgrounds on Canadians and other foreigners.  

then if you like the asset and you will be positive year two that's a no brainer for my way of thinking but most folks on this site are buying in the areas of the country were appreciation is a bonus ( at least that what they have been taught and what they repeat)... so its very foreign concept for them to remotely think about a property that is not cash flow positive day one.

I am not a lawyer, nor do I play one on TV- however, this post on the US Treasury site might help answer your question-http://www.treasury.gov/resource-center/faqs/Currency/Pages/legal-tender.aspxThe way I understand it- if as a landlord, you are considered a creditor, you MUST accept cash.

At the time, we were paying below market rents ($2000/mo vs $2600/mo) and knew that the apartment manager was doing everything in their power to get us to move out so that they could rent to foreign students for the summer (at a whopping $3000/mo!).

For new immigrants and foreign students, I sent them to the local Chase bank, where it was easy for them to get an account.  

I'm not foreign to hard work and applying principles of success. 

They thanked me for the reminders and always paid.But undergrads - unless they are foreign students or engineer students - are a trainwreck.I found MBA students to be short-term renters, but otherwise not a problem.  

With Xero I was dealing with multiple currencies which became a complete nightmare and found a great accountant who sat down and walked me through it.If you find that this is too much work or too difficult you could easily give a bookkeeper a login for you account and they could take over.

While one can argue it is speculative and may not be advisable, it is nonetheless a valid strategy. 2) For foreign investors, it's an indirect play on strength on US dollars.3) Sometimes real estate preserves values better than other more liquid assets (e.g. cash).