Ground beef % ?

I started full carnivore 3 days ago and need to do a food shop tomorrow. I can’t afford to eat steak every single day as I’m a student so opting for ground beef. What fat % should I buy and does it matter if it’s grass fed or not? I’ve been Keto for about a year before this and have always bought 5% ground beef but not sure if I should increase the fat on carnivore? What other meats could I also have for dinner that are not super expensive?