SCHEMA.DBF tells you what files and fields are available to you.  

DETAIL.EXE contains all the dbf files for the information that changes.  

Typically you would make a file of unique reference numbers for the
subset of interest and then use this file to extract the information 
from all of the other files in detail.exe.  For example, if your are 
interested in a particular state then go to the countyd.dbf file and build 
a file of reference numbers where statecd is equal to the state of your 
choice (and the primary flag, or primeflg <> ' '--this eliminates the
duplicates that could occur since one property can be in many counties). 
Now you have a file of unique reference numbers available that allows you 
to extract attributes from all the related one to many files joined on the
basis of the reference number such as apcritd.dbf (applicable criteria)
and archtectd.dbf (architect).  All fields are fixed length there are 
currently no long text fields.


MASTER.EXE contains the dbf files for the static information--codes and 
decodes to use in deciphering the detail.exe data files.

Take what you want and throw the rest away.  

Note to long time users:  Although the data has been stable for over a 
dozen years there have been some recent changes you should know about. 
In concert with a Y2K conversion that lengthened the date fields some 
further normalization of files was implemented and some minor tweaks here
and there such as statecd being eliminated from the propmain state because
it was redundant.  The dbf files reflect current reality--hopefully you 
just pick them up as is without calling any hard-coded routines which you 
might have to change.