Trailer Question

I have a 98 DHM trailer, carrying a Maristar. It is at Copes getting service and they are telling me, I need all new brakes, it has the drums on one axle. They want to charge me $500 to replace everything. My question is, would I be better off, converting to disc brakes? Also, should I convert to electric disc brakes or keep it hydraulic? What would the cost be? It seems silly to pay $500 to replace a bad system when I can upgrade for an additional few hundred dollars. thanks for your help