I dunno, there are a lot of countries that have no way to replace fossil fuel income so they will probably be forced to sell cheap because they spent no time preparing for the future. There will be all this extra refinery capacity too, so I'm not sure prices would ever really spike all that much to matter. The average lifecycle of a combustion vehicle is pretty short so the bulk of gas usage will do down fairly quickly as EVs get perfected and their costs drop well below any combustion option.

You will save money on the purchase, fuel use AND maintenance, so they will get adopted fairly quickly as battery costs decline and first generation bugs get worked out.