I have a total mix in my kit, try and use pro and high end brands but also do use some drug store items that are classics.
Morphe brushes eyeshadow palettes are fantastic when starting out, excellent prices but they are sold out everywhere at the moment!!
My tip when starting out is get your pro discounts in place from nars, illamasqua etc. also try the products on yourself/ truthful friends and then decide whether to invest (thats mainly on foundation I guess) as I could (and I have!!) have wasted so much money on foundations which weren't all that!