Advice on repiping an old multi-family rental property

[Daniel Wang]

We recently closed on a 60-year old 4plx in the Bay Area. Home inspector noted that all pipes are still galvanized steel and recommended that they get replaced with copper. Had a couple of plumbers come and quote, and the lowest number came in above $20,000.

We have very little knowledge about plumbing and are wondering if spending such a fortunate upfront when no serious leakage has been observed is a good idea. All plumbers admitted that the pipes are pretty corroded, and there is one connector in the crawlspace that's dripping water.

Has anyone on the list done a similar project like this? What's the typical life expectancy of galvanized steel water pipes?