PolyGeo provides informal support and user advocacy services, usually on ArcGIS for Desktop, ArcGIS Pro, ArcPy, ArcGIS Online, geoprocessing, ArcGIS for Server Geoprocessing Services, Python and ModelBuilder, via the GIS Stack Exchange, where he is one of its eight moderators. 
profile for PolyGeo at Geographic Information Systems Stack Exchange, Q&A for cartographers, geographers and GIS professionals

He has also submitted many ArcGIS Ideas and is an occasional user of Esri’s GeoNet

However, if you encounter issues which require dedicated resources, such as intransigent bugs needing workarounds devised, or certifying your desktop applications to run at new releases, then such work can be undertaken as a consulting assignment.

Our ArcGIS Specialist has participated in almost every Beta Program from ARC/INFO 6.0 to ArcGIS 10.3, and managed Technical Support of Esri software in Australia for seven years.