A couple of years ago, prior to Amendment 64, we rented one of our houses to two professionals who had their medical cards. 

I am still waiting for a case to test some of these laws based on the first amendment and free speech.

And under Revenue Procedure 2010-13, you can make the election retroactively (typically requires amending a tax return just for the election).Disallowed losses prior to grouping your rental activities together are suspended if you also claim the real estate professional designation with material participation.

Then just amend it to be assignable to Bob.

Parents shall not lease property and leave children under the age of 21 by themselves overnight.RISK OF LOSS AND INDEMNIFICATIONGuest agrees that all personal property, furnishings, personal affects and other items brought into the Property by Guest or their permitted guests and visitors shall be at the sole risk of Guest with regard to any theft, damage, destruction or other loss and Rental Agent shall not be responsible or liable for any reason whatsoever.Guest hereby covenants and agrees to indemnify and hold harmless Rental Agent and their agents, owners, successors, employees and contractors from and against any costs, damages, liabilities, claims, legal fees and other actions for any damages, costs, attorney’s fees incurred by Guest, permitted guests, visitors or agents, representatives or successors of Guest due to any claims relating to destruction of property or injury to persons or loss of life sustained by Guest or family and visitors of Guest in or about the Property and Guest expressly agrees to save and hold Rental Agent harmless in all such cases.RELEASEGuest hereby waives and releases any claims against Rental Agent, the Property owner and their successors, assigns, employees or representatives, officially or otherwise, for any injuries or death that may be sustained by Guest on or near or adjacent to the Property, including any common facilities, activities or amenities.Guest agrees to use any such facilities or amenities entirely at the Guest’s own initiative, risk and responsibility.ENTRY AND INSPECTIONRental Agent reserves the right to enter the Property at reasonable times and with reasonable advance notice for the purposes of inspecting the Property or showing the Property to prospective purchasers, renters or other authorized persons.If Rental Agent has a reasonable belief that there is imminent danger to any person or property, Rental Agent may enter the Property without advance notice.UNAVAILABILITY OF PROPERTYIn the event the Property is not available for use during the Rental Term due to reasons, events or circumstances beyond the control of Rental Agent, Rental Agent will immediately return all payments made by the Guest, whereupon this Agreement shall be terminated and Guest and Rental Agent shall have no further obligations or liabilities in any manner pertaining to this Agreement.ADDITIONAL TERMS TO THE RENAL AGREEMENTIn addition to the standard terms included herein, Guest acknowledges and agrees that the following additional terms and conditions apply to the Guest’s rental of the Property:GENERAL PROVISIONSThis Agreement contains the entire agreement between the parties with regard to the rental of the Property, and any changes, amendments or modifications hereof shall be void unless the same are in writing and signed by both the Guest and the Rental Agent.This Agreement shall be governed by the laws of the State of New York.The words “Rental Agent” and “Guest” shall include their respective heirs, successors, representatives.The waiver or failure to enforce any breach or provision of this Agreement shall not be considered a waiver of that or any other provision in any subsequent breach thereof.If any provision herein is held invalid, the remainder of the Agreement shall not be affected.Any notice required to be given under this Agreement shall be in writing and sent to the contact information included herein.This Agreement may be signed in one or more counterparts, each of which is an original, but taken together constitute one in the same instrument.Execution of a digital signature shall be deemed a valid signature.Security - There is currently an outdoor security camera to protect home during periods property is empty.Pets – provisional with approval and pet feeGuest is responsible for cleaning up any/all pet refuse.

If not, do I go back and amend returns?

In Missouri there is no such law and you have to turn back to the 4th Amendment.

In the US, most areas use some version of the International Building Code with local amendments.

I always keep my listings Active, still showing through the inspection period, although amended to state it is contingent on a home inspection. 

That's just the parts that destroy the Second and Fourth Amendment of the Constitution.