Is the most dangerous phrase in the English language.
The law you are referring to is the Protecting Tenants At Foreclosure Act. Enacted in 2009 it expired in 2014 and I believe it was extended once for 2015.
In 2018, as part of his deregulation package, President Trump extended the PTFA permanently.
SEC. 304. RESTORATION OF THE PROTECTING TENANTS AT FORECLOSURE
ACT OF 2009.
(a) REPEAL OF SUNSET PROVISION.—Section 704 of the Protecting Tenants at Foreclosure Act of 2009 (12 U.S.C. 5201 note; 12 U.S.C. 5220 note; 42 U.S.C. 1437f note) is repealed.
(b) RESTORATION.—Sections 701 through 703 of the Protecting
Tenants at Foreclosure Act of 2009, the provisions of law amended
by such sections, and any regulations promulgated pursuant to
such sections, as were in effect on December 30, 2014, are restored and revived.
(c) EFFECTIVE DATE.—Subsections (a) and (b) shall take effect
on the date that is 30 days after the date of enactment of this Act.
The PTFA has otherwise remained unchanged and can be read in its entirety at:
http://www.nhlp.org/files/Public Law 111-22 title VII as amended1 final.pdf
I'm still not clear on what fair rental value has to do with your situation so let's have you answer a couple of questions.
1 - Did you have a written lease?
If yes, go to question 2. If no, skip question 2 and go to question 3.
2 - What where the actual start and end dates of the lease?
3 - How much was your monthly rent.
4 - What was the exact date of the trustee sale? That's when the bank got it back or somebody bought it.
5 - If somebody bought it, do they intend to occupy it as their residence?
6 - Were you given written notice that your tenancy was being terminated. If yes, upload a copy, redacting any identifying information.
Be specific with your answers. I may have more questions.