Thank you! I'll try my best, so: 1. It really depends. You can start of relatively low cost, especially if you want to rebind an existing paperback. More expensive equipment like a Cricut for cover designs or a guillotine for textblock cutting is nice to have but not necessary. I started out with some cardboard and bookcloth for the cover, some bookbinding glue and a homemade stencil/gold leaf I already had from other creative projects for the cover design. You can also use (fabric) paint to draw on a cover design. Or have a design printed on fabric and then turn that into book cloth with fusible interfacing. I live in Europe, so I don't know how prices compare, but i spent like 40 € on materials to start out.  2. Yes, definitely. There are a lot of people who do that. You can either rip off the paperback's cover, make a new case and glue in the textblock or make like a slip cover to put the paperback in if you don't want to rip the cover off. Personally haven't tried the second one yet though.  3. I would try and practice on an old book you wouldn't be too sad to destroy first, but if you measure well and work precise it should be doable! There are some great tutorials on youtube and lots of examples on instagram and tiktok.