It’s nearly impossible for me to get a mortgage because I live outside the US.

You don’t have to stay owner occupied for 2 years, that would be impossible for military - as anyone in the military will tell you.  

Other realtors before my wife became one told us that it is almost impossible to find any MFH's in the MD/DC area because everyone wants them.

It's almost impossible to get into any property that won't need any repairs on purchase.

If this family is active duty it is unlikely (but not impossible) that military service is affecting their ability to pay rent.

I would shoot for only 2% or better but that would likely be impossible in many cities with a hot market these days .

It's a numbers game so it's not impossible, you'll just have to shift the numbers & resources to your side. 

Not to say that it can't/won't happen, rather it's nearly impossible to put a timeline on it.Plus even if there's a decline some areas are seeing huge growth, so something like 30% drop on equity might only be a few years of less of equity depending on the deal.Historically we're due for a correction, but it's unlikely to be what we saw last time around..

I'm not saying it's impossible, we just had a similar situation with a client and we were able to get him under contract, your agent will definitely need to know how to maneuver this issue and find ways to make your offer more enticing, whether is by waving contingencies, offer a higher down payment, etc, not saying these are the best ideas, but just some ideas to ponder. 

While the owner occupied commitment is one year, it is almost impossible to get out that quickly: new mortgage, find a place, move and so on.The numbers will also look different.