How to manage the car purchase? Red numbers problem!

Hello your ***ed by Puntomaniac*** I have to buy a new used car and wonder how I manage it! Red numbers are no longer given because the dealers don’t give out/ lend them anymore. Get red numbers from the registration office, don’t go, because they want to know the number today, I let myself be told. I don’t know yet, or I have to sign off my old one first? I thought I would pack the money, and then go to the dealer or where a s If you buy a car at the dealer’s, where you buy it, this one gives you the red number? I fluctuate between golf 5, 1.6 liters gasoline, automatic or a Ford Fusion 1.6, automatic… or both, each with 4 doors….budget up to 4500 euros…actually.. How do I manage the thing best? Don’t buy a car so often…