Housing Survivors of Major Disasters Act of 2021 This bill makes certain individuals and households eligible for housing assistance in connection with a major disaster, including Hurricane Maria of 2017. To be eligible, an individual or household must be (1) residing on property located in the area for which the major disaster was declared but does not have documented ownership rights to and is not renting such property, or (2) residing or have resided in an area for which the major disaster was declared during the designated incident period. The Federal Emergency Management Agency (FEMA) must consider alternative forms of proof to determine the eligibility of an individual or household for assistance. FEMA shall create and distribute a declarative form statement that applicants for assistance can use to self-certify eligibility for assistance and shall make the statement available in specified languages at all active Disaster Recovery Centers and on its website and social media. FEMA may provide financial assistance for repairs to ensure that residences are habitable during longer-term recovery and for permanent housing construction if the President determines that such assistance is a cost effective alternative to other housing solutions. FEMA shall conduct an analysis comparing the costs, benefits, and effectiveness of assistance provided under the Disaster Housing Assistance Program, including any case management services provided, with other temporary housing options provided by FEMA.