My first suggestion, surfer-joe beat me to it.
OK on to plan B:
Couple of questions -
1. what piece(s) of equipment are you going to use?
2. How much of the house is full of contents? And what kind of contents are
they? That may sound simple, but I have had my rear end handed to me
because I did not estimate the amount of personal contents that were left
in the house. Clothing, furniture, appliances, junk - adds volumne.
3. What will you be using to haul the debris? Roll-offs or dump truck?
4. What is the tipping fee at the landfill?
5. Hard bid or unit price contract?
6. Will you be allowed to bury the concrete, brick, stone foundation back into
the basement hole.
7. How far is the borrow pit for the backfill? How much, if any, do you have
to pay for fill?
The answers of those questions will have an impact on the cost.
If I was going to give an estimate for this house demo -
6-8 30CY cans worth of trash, 7-8 tons each box
5-6 Tri-axle loads of concrete/foundation material - if you can't bury it
Backfill- would have to look at the site and see how the owner wanted the finish product.
Time:
If you had a 315/160 size hoe, you should be able to get it all down in a day, and finish the haul-out of the debris the next day. 2 days tops. Of course this depends on the amount of cans/trucks you have, distance to the dump and so and so forth.
On my last demo job (
https://www.heavyequipmentforums.com/Forum/showthread.php?t=6922), I had 6 - 30CY boxes of trash, 1 tri-axle load of trash, 4 tri-axle loads of brick and concrete. This house was on a crawl space with brick piers and a 1/2 ass continuous footing. I had to use my loader since my hoe was down south at the beach. Since I had to use my loader, there was more dirt than I would normally put in the trash boxes.
This is the mistake I made on this one: The house was burned pretty well, or so I thought. I looked in the front of the house (it was boarded up pretty well) and I could see bare studs in the living room and front bedrooms. OK, I thought pretty simple. Well the problem was the rear bedroom and kitchen hadn't burned much. So all the appliances, cabinets etc in the kitchen were still there. Also there was a storage room on the back of the house full of clothes, boxes and other junk.
My bid for this job was $4600. It took 2 days to demo and clean everything up. I used my roll-offs and my tri-axle. Luckily I have an inert pit to take the concrete, brick, etc to that didn't cost me a dump fee. I had 6 30's full of trash that averaged 6 tons each.
6 tons @ $18 per ton, 6 boxes = $648 in dump fees.
2 days, 8 hours each, 2 trucks (roll-off and tri-axle) @ $75 per hour = $1200
953C, 2 days, 8 hours @ $125 per hour = $2000
Total = $3848
Profit margin 16%
(didn't really use the mini-hoe, so didn't include it)
My bid was $4600, so not too bad, considering that I got normal hourly rates for the trucks and equipment. This job should have been $6000, for a better profit margin. (35%)