Quote:
"[Q:] How Much Does It Cost To Build a Retaining Wall?
[A:] Differences in size, material and terrain result in a tremendous variety of construction costs. for the sake of this cost guide, lets consider the cost to build a 50 ft long, cast concrete retaining wall.
On a national average, most people will spend a minimum of £9,870 for a 6 ft high retaining wall. For an 8 ft high retaining wall, homeowners will spend around £10,564 Steep land, top-notch materials and/or a particularly higher 10 ft wall can cause the price to climb as high as £19,344.
You could also end up spending more if extensive clearing work for trees or brush proves necessary, or the area is difficult for workers and heavy equipment to reach."
[I've tidied that text up a bit, as it seems to have got rather muddled in its original form]
Source:
https://gradedtradesmen.co.uk/price/how-much-does-a-retaining-wall-cost
See also here:
https://www.mybuilder.com/questions/v/196/how-much-to-build-a-retaining-wall-12-mtrs-long-and-6ft-high-soil-would-be-to-top-of-wall-at-rear-and-the-soil-in-front-would-need-removing-only-after-a-ball-park-figure