Divide 1.4278 trillion won by 3,856 units and the job prices out at roughly 370 million won of construction cost per home [12], which is what it costs to put the building up and not what anyone will pay to live in it. The gap between those two numbers is the whole reason a redevelopment union exists, and the announcement leaves that gap unaddressed [5][4].
It also does not say who books what. Two contractors share one 1.4278 trillion won figure [5], and the release does not specify how it splits between them [15]; a nominal even split would drop about 713.9 billion won onto each order book [14], which is a guess wearing arithmetic's clothes and should be read as one. That absent term is the most interesting line in the release, because it is where you would find out whether this is two builders sharing a job or one builder renting the other's record. The Lotte official's phrasing about bringing together "the construction experience and technical capabilities of both companies" [10] tilts toward the second reading, given that the company describes the contract as its first in public redevelopment at all [8].
The rest of the proposal tells you who the audience was. A complex named TRE VISTA, from the Italian for three and for view [6], sunken gardens, a large plaza, a walking trail of about 4.5 kilometres and a sky lounge on the 32nd floor [7], all of it justified by sightlines over the Anyangcheon stream, Mount Suri and the city centre [16]. That is a consumer brochure, not a bid document, and it is priced into a number that the residents then approve in one sitting.
This is probably wrong, but the structure looks less like risk-sharing than like tuition: Lotte pays away half the revenue to get into a category where it has no history [8], and what it buys is a co-signer on the proposal. Or rather, the more interesting version is that a 19-building scheme rising to 49 floors [4] is one the union wants two balance sheets behind, and the consortium was simply the price of being credible in the room. The dullest reading is probably the strongest, though: past a trillion won, a single site is large enough that two of the country's biggest builders would each rather carry half than all.
What separates those readings is Lotte's own follow-through. It says it will stand up a dedicated team and add an urban public housing complex near Yaksu Station in Seoul and the Myeonmok District 9 project to its public redevelopment book [9]. Bid either of those alone and Anyang was entry pricing, a one-off purchase of a reference project. Bring a partner both times and the consortium is the operating model for anything at this size, which would mean the largest builders have decided that scale on public-led work is worth more than the margin they give up to get it.
