Another librarian, and I've got to say that I find HOP to be too pricey for its value. Most of the public libraries I've worked at bought it only because patrons demanded it, but almost every patron who took it out disliked it, because as Harley said, it is VERY time-consuming to do according to the instructions. I don't have experience with YBCR, but if it is sight-reading, I'd have reservations. IME, phonics is always key to early reading skill.
You really don't need to buy a "program" as long as you work up the concepts a bit at a time. Go buy a couple of phonics books from a teacher supply store and look at the order in which the concepts are introduced. Then read to them often and from a variety of books, and work the lessons into the reading. Let them finish sentences, supply words, sound things out, and connect the pictures to the words in context. I had mine reading at three this way; we just kept at it as a constant game.