FHA security instruments require a borrower to establish bona fide occupancy in a home as the borrower’s principal residence within 60 days of signing the security instrument, with continued occupancy for at least one year.Any person individually or jointly owning a home covered by an FHA insured mortgage in which ownership is maintained may not purchase another principal residence with FHA insurance, except in certain situations as in relocation outside the commuting area of the original home, an increase in family size, getting a divorce from the co-borrower on the original FHA property, or was a non-occupying co-borrower on the original property.Those are excerpts from the actual FHA manual.  

I converted my former primary residence to a rental due to employment relocation for about two years now. 

@Jason Hull  Hey man, not sure why it took so long for my email to let me know you responded to this.

So my brother is about to graduate with his PhD in engineering and is looking to buy a MFH when he relocates for work.

The exception to this rule appears to be in the case of relocation or there is sufficient equity in the initial primary residence (vacated property used as rental) to protect against a default.

I'm also fairly new to the areas that I'm investing in CT since I relocated here from NY.  

Others don't want the responsibility of owning a home, or do not have careers stable enough to guarantee they won't have to relocate one or more times.

It's important to mention that I'm stuck in CT for at least another 9.5 years - at which point I plan to relocate to a less-taxed, smaller-government state.We have agreed that we are out of space at the Bunny Ranch (if my wife reads this, I'm dead), and have begun casually browsing for the next castle.

and were not preparing to relocate to PA?

Some may not know this, but in Seattle the owner also must apply for a Tenant Relocation License if you'll be giving a tenant notice due to a remodel.