Initial milestone would be a weekly rate, from the beginning of each week. Your mafia RPG should be ready within 360 days and contain a minmum of 20 hours.
You could expect concept reports and team assembly reports in the first month, followed by developmental reports for each of the following months with an overview at 6 months. Beta testing would occupy the final month at least.
You'll gain full rights to use/redistribute the game as your own. The development team member would retain their individual rights to reference and showcase their work. You may opt to aquire the game brand-free, in which case only individual names would be listed in the credits, but you would be required to pay a 10 percent fee on all profits made by game sales each year, or branded, in which case the team would gain the right to promote their brand at the start of the game and in the end credits with an mentions selected by the team.