A deceptive way of selling that involves advertising a product at a very low price in order to attract customers who are then persuaded to switch to a more expensive product WordNet 3.0 & Open English WordNet

Bait-and-switch is a form of fraud used in retail sales but also employed in other contexts. Wikipedia

A form of fraud Wikipedia Disambiguation

Form of fraud or false advertising. Wikipedia Disambiguation

A form of fraud used in retail sales but also employed in other contexts, typically involving enticing purchases of substituted goods by unsuspecting customers Wikidata

An unscrupulous and sometimes illegal sales technique, in which an inexpensive product is advertised to attract prospective customers who are then told by sales personnel that the inexpensive product is unavailable or of poor quality and are instead urged to buy a more expensive product. Wiktionary

Sales technique. Wiktionary (translation)