Though I didn't even make any fb app, you can consult with other app owner. I think you will get some ideas from them if you ask gently
It depends on the size and features you want. I suggest you to consult with the "facebook developer consultant". Just google it and you can find some of the companies who develop facebook apps.
i don't want to spend a lot of money for an application i need an application that can make money in the future . if i want to create application with free software own facebook does it work ?
i need one application entertainment for around the world then can make money through that.i want to spend about $300 for it
You can create your own but if you're looking for a professional application such as a game then it will be costly especially if flash is involved. If you plan on making it big then it can be a good investment. Start googling "Facebook application service". Here is the first result I found: http://www.facebookguru.net/facebook-application-development.php (not mine). Could help.