Okay, I will convey this to him and see what he says.

After taking into consideration all of the things he said, I wrote out 5 or 6 drafts of the letter, all very different but conveying the same message.

Or, on Acris go to search by document type and then look at deeds and other conveyances and see if the property has been conveyed to the city. 

It's hard to convey just how much the RSO (rent control board) is, pro-tenant and anti-lanlord, to out of state investers.We inherited a condo in a rent controlled area, and didn't know it was rent controlled.

And what lesson does it teach to convey the message that no matter how great a tenant you are, I'm going to "reward" your good habits and behavior with an automatic rent increase?

Explain who wants to convey the property to you through a quit claim deed, if they will insure it you should be ok to purchase the property. 

Once he conveyed his intentions, he was threatened with removal of the tenant. 

The Seller (Vendor) retains legal interest in title and is obligated to the conveyance terms within the contract.  

My guess is that an attorney (which I am not) would recommend one of two things: Either you and your spouse holding title as tenants-by-the-entirety, or in some kind of trust.The specific deed conveying title may be a Quitclaim deed or a Warranty deed, depending on how your spouse's interest was acquired, and is not exactly the same question you actually seem to want answered, i.e., the best form for you to hold title based on your circumstances.As you may have expected when starting a post with "I am looking for legal advice", I'll give you the disclaimer that "I am not an attorney" and the standard - and in this case sincerely given - advice "you should seek an attorney to help with your specific situation".An attorney is almost certainly not going to post an answer here without setting up a consultation to review your (and your spouse's) specific situation, though you may get a few who post their qualifications and invite you to contact them privately.

Generally, an addendum will supersede anything stipulated in the original RPA, so I would assume title is being conveyed with a QCD.