I agree the fish should go to good homes regardless of what people are going to give for them. Don1 One thing is for sure, that the late owner cherished them, his tame koi are testiment to their well kept conditions. For all the money you are going to get for everything, fish, filters, it wont cover the cost of re-landscaping a pond of that size. Plus koi in an established pond will freak out as soon as a net goes near them, if the water is green, you may not see them for days! if they are spooked. It means you would have to drain the pond to see them. Can you see where this is going? You have your work cut out, catching, sorting, dismantling, landscaping. I would leave it all in situ.