Creative Landscaping N Irrigation

Alex and Gary installed my Baseline 3200 system. Gary was factory trained on Baseline installation and so seemed a good choice.
After they were paid in full, the system displays errors and will not operate two zones. After repeated attempts and messages left there is no response from Gary or Alex.
Was told I would receive a document on all the in ground sensors installed and after they were paid in full. Gone!
Poor service not warranty on workmanship, no response after paid.
Things I wish I had done,
Get it in writing:
1. Scope of work, written proposal with property diagram showing what they intend to install and what sensors will operate what zones.
2. Terms of Payment — pay 90% upon completion and successful demonstration of system. In my case they said everything worked and then next day it didn’t. Pay the 10% retainage only after 30 days of trouble free successful operation.
Do not pay for partial work because you have no way of knowing if it will even operate until finished. Don’t fall for the line — «my men need to get paid».
3. Stated warranty — How long and what will warranty cover.