According to a reviewer of the film in the September 30, 1957 edition of Daily Variety, in the novel upon which this film is based, the family looking to move into the neighborhood was African-American and not Japanese-American as depicted in this picture.
In 1967, musician David Bowie cited this film in a letter to fan Sandra Dodd: "I was watching an old film on TV the other night called "No Down Payment" a great film, but rather depressing if it is a true reflection of The American Way of Life."
When Troy tells Jerry he's been saving up "green stamps" when asked about if he's going to buy a station wagon, he is referring to S&H Green Stamps, a retailer customer rewards program. It was one of several customer incentive programs at the time, where stamps were issued to the buyer at the cash register in denominations based on a percentage of the purchase. The stamps would then be pasted into collection books which could be exchanged for merchandise at S&H stores or via a catalog.
The housing development shown in the film as "Sunrise Hills" is the Marquez Hills neighborhood in Pacific Pallisades, Los Angeles California. In the first half of 2018, the median sales price of a house there was $2.7M. A lot of the houses seen in the film have since been torn down and replaced.