PHP debugger

There are many threads on PHP editors but none on debuggers. I tried Maguma Studio and PHP Expert Editor. On my computer I installed Apache and MySql servers. I think the programs woundn’t work because of the database. What debuggers do others use that have documentation and are inexpensive? I also can not use the remote access feature since file access via “include” or “require” functions with HTTP or FTP are not available on Windows and my computer has Windows. A little known fact. These programs have little documentation and poor tech support.