When you say $3,500, do mean he's going to pay you or you have to pay him? Sorry, old joke.
I'm a big fan of recycling. My last project was
remodelling my home with nothing but materials purchased on Craig's List, Ebay and second hand shops. I spent a whole summer just buying used materials. For what it's worth I learned was recycling is expensive.
Retail new costs
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$400 liner
$500 two 6000 gph pumps
$500 local rock delivered
$300 Arkansas flat rock
$20 Crappie and catfish, or free from local lakes and ponds
$200 9" Koi (not sure how many) I guessing these aren't Grand Champions
$100 skimmer
$400 300 gal Rubbermaid trough
$100 plants
$20 per lily
$0 waterfall
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$2,540 full retail
- 50% used value
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$1,270 best case value
- ??? tear down cost
- ??? transportation
- ??? oops, couldn't use that
- ??? oops, fish all died waiting for new pond
- ??? oops, didn't see that coming
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$deep dark hole of despair
The price I'd charge to tear down that pond would be in the $2,000 neighborhood and I keep whatever I can. The rocks would be left in the hole and covered with dirt.
Rocks, are free for the most part. The cost is in digging it up, crating it, transportation and overhead. You're doing the digging, crating and transporting.
I've picked up rocks for free off Craig's List. Dumpest thing I ever did. Gas, wear and tear on my truck, time, no where close to worth while. If they were next door, and free, OK.
That $300 a pallet Arkansas flat rock...after you dig it out of that pond it isn't going to be Arkansas flat rock any more, it's going to be slime coated black flat rock. No value. And getting it out of that pond is going to be a nightmare. By slabs I assume big, heavy. Working in the bottom of a pond is grease on ice. Putting large dry rocks into a pond without damaging the liner takes some experience...getting them out, nightmare.
If you do this I suggest plan B is to bring a sledgehammer and give the slabs some hits to break them into smaller pieces you can manage. Breaking them won't damage the liner but you have to be careful picking them up as they now have very shape edges.
The chance that the hole in the liner for the skimmer(s) will line up in your new pond is zero. So the useable liner size will be less than current. Most people buy a liner several feet larger than needed. Filling in a pond to make up for being short on the liner, now that's a job.
Pond plants reproduce fast (or die). So even a $100 worth of plants will normally fill a pond in one year.
The waterfalls have no value. The chance of reusing that liner is near zero. Maybe in a much smaller application.
The price I pay for used material is around 10% of retail for most items, depends on item. After tossing the things I couldn't use afterall, or were in worst condition than I thought, my time screwing around to get things to work, was it still ended up costing more than retail. I do it for other reasons. Many sellers get really mad and say you're robbing them but I'm not here to turn their problems into my problems. And I never force anyone to sell. They're grown ups.
It may sound harsh but I think it's a reality. A reality I learned the hard $$$ way.