Conservatorie question for builders and fitters?

Question:if u were going to assemble this conservatorie for us how much would u have charged,just trying to find out if i have been ripped off or not,check out the link(www.palladium conservatories.co.uk/ victorian/ victorian-full-height- with- base,htm (i will let u all know how much i was charged later coz im sure ive been scammed
ps the builders told us they needed to build a retaining wall underneath but when i came home from work they hadnt done one,just assemble the conservatorie and still have charged me the same price without a retaining wall,these guys didnt have to spend any money on any extras,so what they money they make goes into there pockets,and it was 3 of them on a 2 day job,the conservatorie is the top picture v1,type the link in as one word as i had to space words out to fit it all in

Answers:
In the US I would say it would be about $10,000 to $15,000. Hope That helps some.