A few years ago, I spent most of my savings on The Lunar Chronicles by Marissa Meyer (Cinder, Scarlet, Cress, Winter, and Stars Above; I didn’t get Fairest), read them all, and loved them…though I didn’t reread them and sold them some time later.
And what was the first series you spent most of your savings on?
Other than the usual trilogies, The Hitchhikers Guide to the Galaxy. My longest series was The Dark Tower by Stephen King though.