Gulfstream 3 pilot reported during a reposition flight to a maintenance facility; they had multiple system failures. One year later after repairs were accomplished to aircraft; the pilot refused to fly the aircraft due to not being airworthy and not having a ferry permit.

Narrative

On Day 0 and then Day 2 I was contracted to fly a Gulfstream from ZZZ to ZZZ1. I had previously delivered the aircraft to ZZZ to install a new interior as well as perform other required maintenance. This last flight was performed last year. At the time the aircraft windshields had gotten so bad; you could barely see out of them and I explained that when we land in ZZZ they will need to be repaired or replaced.During the flight we experienced multiple compound failures of systems; specifically; both windshield heaters failed in flight; the left windshield heating element failed in flight. We experienced a Dual generator failure; necessitating using an emergency Transformer Rectifer Unit (TRU) to complete the flight. While climbing out in IMC we lost both gyro systems. We also lost a fuel pump as well an intermittent failure of an alternator. After managing to arrive in ZZZ; I gave a detailed list of repairs that need to be resolved before future flight. Any future flight would require a ferry permit. Nearly a year later; I am again asked to fly the aircraft to ZZZ1 as it will be based out of ZZZ1; At that time I was told the entire interior was replaced and every item I presented to maintenance was repaired. There was several delays because when I inquired about the aircrafts readiness; more maintenance items need to be addressed; such as the flaps would not operate in certain configurations and there were numerous fuel leaks in the wheel well.On the day I arrived to inspect the aircraft; the lead mechanic said more items were not working; specifically the APU generator as well as the must have TRU. In all total more items were failed since its last flight. I advised that to ferry the aircraft we would at a minimum need both generators working and a working TRU. We would also require a ferry permit to fly it with so many other failed components.After I left the lead mechanic texted and called me and attempted to bully me into flying the aircraft in its present state. I said I would fly it when both generators were working; the TRU was replaced and they had a Ferry Permit.It is my understanding they partially took my advice. They acquired a working Generator; a working TRU but no ferry permit. It is my understanding they hired a new crew to fly the aircraft with the minimum repairs I suggested but without a proper ferry permit.