I actually was just running into this problem this week, but on Kindle/eReaders. The solution I found was getting a out-of-state library card to a big city library ($50 a year) and borrowing books. The library also has all the manga that I wanted to read available to borrow with 3-4 copies of each volume, which ensures that I'll always be able to check out one of the ebook copies and put it onto my kindle

I highly recommend this to anyone, not only for manga but for any ebooks