Yes, we have actually seen some pretty ugly stuff like you mention. Equally bad is "1/2 street" or even "1/8 street". I work for a private company that consolidates public record data for about 1/3 of wisconsin (and growing). Unfortunately, addresses are quite ugly, and we need to build special cases for junk like this thread is about.

We currently have a few thousand lines of perl to parse addresses, and it's integrated with a CASS certified (U.S. postal certification) address correction software, but it's still a big pain.

The worst part about the whole deal is that the government raw data is sometimes truly ambiguous, such as "814 E main st". There's generally no good way to tell whether the "E" should be a unit or a street directional. So then we try both cases against the address correction software, and hopefully only 1 comes back as a match.

Not nearly as bad as a few years ago, when i was maintaining legacy C++ code to try to do this!

Yes we do only have a fixed number of records, currently about 3 million.