I personally would select a smooth tile or laminate surface in your budget instead of carpet. You can purchase puzzle mats or a gorilla mat to place over the surface and provide more cushion for your joints.
+1 to this! The first round of cardio and the first round of core felt the most challenging to me so I was glad for the 20 rep limit! This was a fun one
@Meldel , I second your request for a Cathe 4x4 workout. In the meatime, I recommend Tracy Steen on YouTube. She has a couple of 4x4 workouts on her channel and they are great to follow along with or to get ideas to create your own 4x4.