Do they need to have been delivered by the association within 30 days or something?

This website has a pretty good explanation of the process you'll follow: https://ipropertymanagement.co...I like your plan of the certified mail notice for 30 day notice to quit, I don't think you need to have someone hand deliver it. 

By contrast, many legitimate, licensed health care professionals deliver services remotely, including over the internet.

My agent brought it to me, was a fresh to market deal and he knew the other agent.

Possession of the Property will be delivered to Buyer on Possession Date at Possession Time, subject to the Leases as set forth in § 10.6.1.1.If Seller, after Closing, fails to deliver possession as specified, Seller will be subject to eviction and will be additionally liable to Buyer for payment of $1 Million Spacebucks per day (or any part of a day notwithstanding § 18.1) from Possession Date and Possession Time until possession is delivered... 

Fresh to market, my agent knew the seller.

(So far the ones I found all have tenants and it seems like not a lot is willing to deliver property vancant)- remodeling would most likely be the cheapest.3) Junior ADU- Have to get creative, find floor plan that works to convert current living space to 24) roomates- Least desirable to meWhat have people been doing for house-hack that have been successful? 

For starters your original purchase and sale contract can be any template, as long as you delivered earnest money and opened title you have equitable interest in the property.

The photo shows a door-clean it and give it a fresh coat of paint. 

I would often sell cheap products from China that could take over a month to be delivered to my customers.