There is no self sufficiency required. 

Quads on a septic system is going to be a major expense and you should expect to pump it out every 2 years or so, so it needs a man hole cover.If it is going to be septic be SURE you have sufficient soil quality for your drain field, you will want lots of sand.

Might be worth simply waiting for current tenants to vacate.Also, in Washington you do have to provide 48 hour notice and if you can get a response to your request for the tour, that is sufficient.

Many investors find out too late that their deal doesn't cash flow sufficiently when using property management, and they themselves don't want to be active landlords. 

Yates A good lease agreement that includes a hold harmless clause should be sufficient.

How did we go from having sufficient housing 5-10 years ago to suddenly having a serious shortage?

Hope this helps to understand how a lender looks at a rental property's income to be a self sufficient asset.

FHA Stress Test (self sufficiency test) for 3-4 unit properties.

Owner agrees to maintain sufficient and prudent all risks property insurance and that the Manager shall be an additionally named insured.

Would a recirculating vent be sufficient, or should I explore other options like a microwave with a vent or a ducted ventilation system?