Demolition cost inconsistent

[SelfBuilder101]

Hi everyone. Sorry if this comes across as quote checking, but I have had some inconsistency from the demolition supplier that makes me worry I am far off market rate. Last year I got a budgetary estimate for demolition of the following:
- demo and removal of 4bed bungalow (85sq.m.) asbestos report done, small amount present
- removal of concrete hard standing 15m x 10m
- removal of 40ft lorry body (don't ask)
- removal of concrete shed
they gave me an estimate of £5,200.

I then had a site visit a number of months later and the cost has jumped to £10,000. The concrete is larger than the initial estimate (got them to put it as 30mx10m), but I have checked and that only runs to about £2,000.

What's going on? Is £10k reasonable for this amount of work or are they trying it on now that I have been keen to move forward. The site hasn't moved and they knew where it is (South Cambridgeshire) so any transport costs won't have risen much. How would a site visit make them double there estimate. Access is really good and I gave them loads of info for the budgetary estimate (including the asbestos report, floorplan and photos).

 

[^woody^]

You need to get other quotes/estimates to compare.

The previous estimate is just that and has no legal basis.

 

[SelfBuilder101]

Thanks ^woody^. I know legally they are fine. I had another visit and quote for £8-9k, so either that's the market rate or I came across as a mug to them as well.