Your closer to the "horses mouth".

I will try to find the best recommendations through word of mouth.

Then, I would tell the tenant that if they think they cannot afford the unit, you would be willing to let them out of the lease with no penalty, providing they give 30 days notice, so that they can find a place that they can afford and be happier in.

But I'm not quite sure how to find the people coming in who would need such a service, beyond word of mouth.

So would you say you bought most of your properties by word of mouth, or did you acquire most of your properties by looking on your own? 

How wonderful that your provide a product that is so good that word of mouth is mostly what you need.

I am a Real Estate Consultant and you took every word out of my mouth...You said it all....Keep up the great work...Representing....Keep making it happen!

You find those with signs, letters, door knocking, word of mouth referrals, website, etc.Happy hunting!

As for buying now and renting until you move, given your timeline of ~6 months you might be happier just waiting.  

Not real estate related but a great book about dealing with adversity in all aspects of life past and present and how to life a happier and more fulfilled life.