I lease and well I went a little crazy when I went tack shopping. Some of the tack that I got replaced old tack that I no longer use. I got a saddle, a bunch of saddle pads, first aid kit, buckets, bath supplies, first aid sprays etc. a bridle, a tack trunk, halters, lead ropes, fly gear, tack cleaning supplies, grooming kit, and any other little odds and ends a horse may need. the only thing i did not buy were a girth which i want to get because i am not a fan of the one he has and i want to get a bit because i want to have 2 complete bridles. so basically i bought everything except blankets as if i owned him.
Your horse is an extension of you.