They agreed on a fair price， 40，000 pieces of gold， and on a date to sign the contract and close the deal.
两人谈妥了一个公平的价钱，4万块金币，并商量好了合同签字的日子。
http://www.jukuu.com/show-contract close-1.html

The project caot be closed until the current operation has completed.
当前操作完成之后，才能关闭该项目。

and in 1990 it was closed as engineers undertook a strengthening project that decreased the lean by 17 in (44 cm) to about 13.5 ft (4.1 m). The work was completed in May 2001.
1990年关闭,让工程师们采取强化措施,使倾斜度减少44公分,减到只倾斜约4.1公尺。2001年5月完成了这项工程。
妥善做好项目收尾工作,以便项目实施进入下一个阶段.
关闭 more'so used as close-out or shutdown. 收尾 is used when referencing contract closing. Go with 收尾 :)

http://www.jukuu.com/search.php?q=关闭 project

close a sale/deal = 达成交易(Google)

终止