Some users have suggested this question and answer, but that asks for an exploit, while I am asking for a way to not encounter this in the first place.
Ok, so we all know the infamous words, "too expensive". I think everyone who has played Minecraft knows what these words mean, and for those who don't, I'd advise you to try and not hit those words, because it makes your life harder. So I was looking around the Internet, and I found out that the anvil hits a certain level cap. And I'm trying to enchant my bow, but I don't know how to avoid those words. Is there a certain way to enchant a weapon so it doesn't become "too expensive"?
For those players who don't know what "too expensive" means, it's when you hit a certain upgrade cap (I don't really know what it's call, so ima call it upgrade cap) on an anvil. So when you use an anvil, each time you enchant a weapon of your chose, the XP requirement will keep getting higher until you hit the "too expensive mark. Even if you have enough XP, it will still say "too expensive", so enchant you gear WISELY.
Best Answer
I'm not sure if this is the best way, but it's how I avoid it.
Every act of enchanting adds an enchantment level to an item, every time you enchant or repair an item with a higher level. it becomes more expensive. I know of two things to avoid this
Start with good enchantments, don't work a fortune I into fortune II into fortune III that takes too many enchantments, get a fortune III to start with, and add something else that's good.
second, the most important part, the game enchants to the highest enchantment level of an item +1. What you can do is start with a pickaxe that already has at least one high level enchantment on it and add a book to that. Your pickaxe is now Enchantment level(EC) 2, Second. Get the next enchantment book, and enchant another book on that book, That book now has two enchantments and is level 2. Add that book to your pickaxe, making your EC3. Next you can make a level three book and add that. And so on until you hit that "too expensive" level. However with some good enchanted books you can end up with some extremely good gear before reaching that limit.
so in short: start with good enchantments, combine enchanted books to the same level as the item you're enchanting before using them on that item.