MODx Revolution is a dream to code, especially with custom databases. I know this isn’t answering your question directly, but give learning it a go before outsourcing, and it will probably save you more time than finding, monitoring, and paying someone else would take up. Here’s a crash-course that worked for me:
Go on GitHub and download the "Doodles" (example custom database) snippet:
https://github.com/splittingred/Doodles. You can test out the Doodles package in the MODx repository to see what it does, but the GitHub version includes the build package. Then use Notepad++ or your program of choice to file search and replace case-sensitively Doodles, Doodle, doodles, etc... with your package name, and do the same with the file names. Finally, edit /core/componenets/doodles/model/schema/doodles.mysql.schema.xml with your database details, update a few other files with the new table field names (especially doodles.grid.js and getlist.php), and run the following files: build.schema.php (which will generate the remaining files you need from your schema.xml file) and build.transport.php (which will generate the package ready for installation).
The first time I did this required a few hours of troubleshooting (I had missed a few words in the search and replace), but now I have a "base" build package to work off of and can make just about any custom database component I need in half an hour of search and replace and tweaking. Whenever I need to add features, I just browse github for other build packages (especially splittingred) to use as examples and add/ remove as necessary. For example, I borrowed heavily from the Quip package to add plugins, events, system settings, etc.... I ended up merging the Quip and Doodles packages for a good level of flexibility.
Once you have the package installed, it’s even easier to access. Refer to
http://rtfm.modx.com/display/xPDO20/xPDOQuery and just replace $xpdo-> with $modx-> to explain the examples you find.
Finally, my 2cents on outsourcing: I have looked to outsource some work when I’ve been too busy. However, people familiar in MODx are rare compared to people familiar in PHP and justifiably charge higher for MODx work. Now that I’ve learned how to make my own custom packages, I can’t imagine spending all that time finding someone
.