Is it permissible to pray Istikhara daily for more than three years before going to work, to seek Allah's guidance in all matters of that day?

Istikhara is a good and legitimate act when intending to do something. It does not have a specific time; rather, it is performed when there is a reason for it, which is the intention to seek guidance regarding a matter. So, two rak'ahs are prayed, and then the Istikhara supplication is recited. Istikhara is not prescribed except out of necessity. It is permissible to perform Istikhara for more than one matter in a single prayer, and the supplication should be comprehensive, covering all the matters for which guidance is sought.