价值 (jiàzhí) is a noun meaning 'value, worth' — it can refer to monetary worth (e.g., of an artwork) or abstract worth (scientific value). 身价 (shēnjià) is more specific: it refers to the worth or social status of a person (e.g., a celebrity's market value). 价值观 (jiàzhíguān) means 'value system' — the set of beliefs about what is important, not individual values.