IRS has indicated they would be generous in determining reasonable cause for penalty abatement requests if returns were not filed timely.Please see this post I made earlier regarding the March 16th date as well as the comment by @EamonnMcElroy regarding small partnerships.https://www.biggerpockets.com/forums/51/topics/816988-march-16th-filing-deadline-has-passed-late-filing-penalty-infoAs always, please consult your tax advisor to make sure your returns are filed properly. 

A vacant property, I would 100% show, but I would put proper precautions in place when doing so.

Proper nutrition, hygiene, and exercise can keep the healthy prepared to overcome the virus. 

Additionally, is there a proper way the tenant must inform me?

@Tyre Carmon:Finding deals that workRenovation: properly estimating costs, construction managementARV: accurately estimating ARV

@Naomi Pinger No, sadly he only wants to stay north of Seattle proper, but thank you. 

As long as it's installed properly you won't need a warranty.

Do lenders actually lend on the income of the asset or it is weighted on the net worth of the borrower, or both? 

If a home is properly maintained, as are some of the ones I buy, you still have original hardwood floors, original joists under the sub-floor, original trusses in the attic, etc. 

Another thought, post on FB Marketplace and see if you can find a sublet or on Craigslist, but make sure you do your due diligence and screen properly - safety first!