Carvana (CVNA), the Phoenix-based online used car retailer founded in 2012, has been grabbing headlines recently. Earlier this week, the company launched a program to make used electric vehicles (EV) and plug-in hybrid buying more attractive for customers with discounts of up to $4,000 for eligible vehicles. Against the backdrop of a growing used EV car market, falling inflation, and the possibility of a rate cut soon, the new offering comes at an opportune time from the company. CVNA’s stock price also got a boost from a recent upgrade to “Buy” from “Hold” at brokerage firm Needham, whose pri…