If you're planning on making it a private program to sell, make sure that you HWID lock the program. Also, make it so that the program changes hash on execution every time. Furthermore, make the movements human. Facepunch wont be able to perma ban you because they would not have sufficient evidence against you. As such, it may be worth starting out by figuring out how to run the program to look like another more common program, such as *****. Good luck!