You know, you really don't need to wait for every detail to be correct before you start building. You really don't need to know how many cars could fit on the auto ramp at the San Jose freight station - by the way, it could fit three - before getting out of that armchair.
Well, you might not need to know about the track arrangements, but wouldn't it be nice to know when they last re-roofed the building, or did foundation work before building that model? Luckily, San Jose now has scans of old building permits on-line. I've already learned that one of the fruit packing sheds on Ryland Street (100 Ryland Street) was torn down in 1972 from its demolition permit, and 200 Ryland Street had its foundation redone when Abinante and Nola was occupying the building in 1944.
If you're modeling San Jose, check it out... and if you're modeling any place else, check whether the local city or town has started putting their records online, too!