The practice of raising prices to keep undesirables out

price out / price out of the market

Transitive. to price out of the market: to eliminate (oneself or another) from effective commercial competition through prohibitive prices; to charge a prohibitive price for (goods or services) or to (the customer). Also to price out (frequently in passive): to charge a prohibitive price to (a potential customer); to prevent (a person) from buying something because of prohibitive prices; similarly to price (someone) out of (something). OED

price (someone) out of the market (idiom)

To make the price of something too high for (someone)

The high rents are pricing some people out of the market. m-w

Although the cheapest three boroughs in 1995 were still the cheapest in 2007, these boroughs had among the highest rates of house price inflation in London in 1995-2007, which has intensified problems of affordability for those attempting to buy, many of whom are effectively priced out of ownership and into private renting or social housing which have both grown dramatically. T. Butler and C. Hamnet; Ethnicity, Class and Aspiration

In Priced Out, Reinhardt offers an engaging and enlightening account of today’s U.S. health care system, explaining why it costs so much more and delivers so much less than the systems of every other advanced country, why this situation is morally indefensible, and how we might improve it. Blurb for Uwe E. Reinhardt; Priced Out: The Economic and Ethical Costs of American Health Care

Like so many longtime residents, Ken agreed that the middle class has been priced out of Stuyvesant Town: The pricing structure, of course, has all changed since when we moved in. R. A. Woldoff et al.; Priced Out: Stuyvesant Town and the Loss of Middle-Class Neighborhoods

Mr. TUGGLE. I think it will be about the same and upward, because again certain qualities are simply priced out of the market, particularly lower quality leaf, and that practice means we are going to price your fourth, fifth, and sixth grade tobacco out of the word market. The problem to me was rather simple. US Congress; Flue-Cured Tobacco Price Support Program for 1979 Marketing Year.