I am a GC/Subcontractor who did Restoration work in New York from 2014-2018. We followed AIA guidelines and the project was valued at well over $1M. The building's project manager passed away and they assumed new management in 2018. We were not paid our final installments and retainage, totaling more than $230,000 which has accrued over $68,000 in interest fees. We were not aware of the mechanical liens back then. We have been emailing for payment and they have not paid. What course of actions can I take (before engaging a lawyer) to collect payment? What grounds do we have to stand on?