The Hep-B vaccine used to cost $100K and now it's about $4000 (in the US where we get screwed). Honestly a $20K vaccine that would protect me from the big killer cancers would be a check I'd write in a second and I'm not a rich man.
I had Twinrix (Hep A+B combo vaccine) at least twice because I'd forgotten I'd had it, and only found out later when I put my medical notes into a spreadsheet.
Just had to ask and the NHS did it for free.