Many of the takers are foreigners.

I have seen countless people lose millions of dollars in real estate - sometimes, literally overnight.Since you are likely to take my comments with a large grain of salt, as you are doing your research and doing your due diligence, ask around for (a) specific success stories that foreigners have had with real estate which resulted in handsome profits and (b) all the failures. 

You have foreign nationals moving here that can't qualify for a bank mortgage, yet they have the cash for a down payment in that neighborhood.

Target big corporations who need the space for remote clients or consultants, investors (foreign), etc.  

They cater to lending for Canadians and Foreign Nationals, as a matter of fact, that's all they do. 

so long story short tenants dont have soc security numbers so screening them became tougher and other than not allowing foreigners to rent i dont know how you can adequately screen them

I feel your pain.Honolulu is a hot market with a lot of foreign money coming in, and that foreign money seems to be hitting the MLS.

We had to deal w/a foreign investor and we learned a lot through that process.

If you do one deal, that may work without servicing issues, if you plan on doing this over and over, you will have lending issues.Costs of filing a foreign corporation is often more than domestic entity, an entity will need to be registered, one way or another in the state where the property is located to act in matters related to the property.

Look it up here on BP if the term is foreign to you.If your finances are in order (clean on paper), explore what programs are available to you for a primary residence.