What's the most expensive thing in Adopt Me?

So, I'm curious to know, what exactly is the most costly item or asset one can acquire in the game of Adopt Me? I've heard rumors of rare pets and exclusive items fetching exorbitant prices, but I'm genuinely intrigued to find out which one takes the crown as the most expensive. Is it a specific breed of pet that's highly sought after? Or perhaps a limited edition item that's incredibly difficult to come by? I'm eager to learn more about this intriguing aspect of the game.