Looking at your situation the red flags to me are that you have not shown any substantial ties to your home country. If a car or a business is not in your name essentially they are not yours. You need to get them changed to your name. Travel history. You have to travel to a European country. Even though your brother is paying for everything you must show that you have money in your bank otherwise they are thinking he doesn't have money so whats to stop him coming here and staying. You cannot work while you are there either so mentioning anything that remotely looks like working, even if its unpaid is a red flag.