In this fanfiction, Harry Potter might be facing a new situation in the Muggle world. Buying a car could be a sign of his further integration into Muggle society. Maybe he uses his wizard money to buy a really cool and unique car, like a classic convertible.
Maybe Harry buys the island to get away from the wizarding world chaos. He could build a peaceful retreat there, away from the Dark Arts and all the drama at Hogwarts.
Well, it could mean that Draco is interested in exploring different perspectives on Harry. Maybe he wants to understand Harry better through the fan - created stories. It could also indicate that he has a new - found appreciation for Harry's character or the whole Harry Potter universe in a different light.
Yes, there might be. The Harry Potter fandom is vast, and fanfiction writers come up with all sorts of creative and unique ideas. You can try searching on popular fanfiction websites like Archive of Our Own or Fanfiction.net. There could be a story where Harry Potter is involved in buying a marriage contract in some alternate universe or as part of a very different plotline created by the fanfiction author.
Freedom is also prevalent. Just like how a motorcycle represents freedom in the Muggle world, in these fanfictions, it gives the characters a sense of liberation from the constraints of Hogwarts or the wizarding society. For example, characters might take off on the motorcycle to have some time alone or to break the rules in a harmless way.
Maybe some of the Hogwarts professors. For example, Dumbledore could have given Harry some advice about the island before he made the purchase. Or Hagrid might be interested in the island's magical creatures, if there are any, and could visit to study them.
He could use the money left to him by his parents. They were wealthy and it's likely there was a large inheritance waiting for him. Plus, he had his own earnings from winning the Triwizard Tournament.
Ron might be there too. He could use his skills in handling magical creatures to populate the island with friendly ones. And he could also help with fishing in the surrounding waters using magic, providing food for those on the island.