This achievement will unlock once you have earned $500,000 in the game.
You earn money two different ways in Parking Mania. On each level you are assigned a number of goals (the number varies by map, but ranges from 1-4). Each goal you complete will reward you with money. Easier goals and lower levels generally pay less, while harder goals and higher levels generally pay more. The other way to earn money is to collect coins on each level where they are available. Every coin you collect will increase your earnings by $500. If you are aiming to complete all achievements in the game, however, don't focus on coins after you unlock Jackpot as they will slow you down and you will earn far more money than you can spend just by completing the 160 levels needed for Parking Pro.