Some 5,318 people who engaged with Threshold during the summer were at risk of losing their homes according to the housing charity's third quarter Impact report.
It is the third consecutive quarter that saw renters at risk because their landlords wished to sell, according to the report.
Queries regarding tenancy terminations rose by 14% in the third quarter this year compared to the same period last year.
General termination queries and questions regarding standards of accommodation ranked among the top concerns raised by renters who got in touch with Threshold between July and September.
Between April and June, 4.5% of queries related to accommodation standards; queries about standards rose to 7% during the summer.
There is a minimum set of legal standards by which landlords must abide. People contacted Threshold regarding mould and broken heating systems.
The charity has proposed a new "NCT-style system" for housing that would ensure accommodation standards are met.
Threshold supported over 900 households to stay in their homes or secure alternative housing, preventing them from entering homelessness, with 1,333 adults and 939 children supported
Almost 9,000 households were supported by Threshold's advisors on wider issues regarding tenancies.
