Find and Repeat Value

This could be done in a DAX column if you first add an index, but here is one way to do it in the Query Editor.  To see how it works, just create a blank query, go to Advanced Editor, and replace the text there with the M code below.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8kxxKs3MScnMS1fSUQoGUjmpIZUFqUBOQFFmcqpSrE60kiGQF5RanJmSmleSmZgD5BkaGcBlnPNzc1OLkqESpgiJgMSibIi5SIL+aWkgY4FipmAxIyDTI7+4ILMErN8IqtQIRb8hRK0xWG1JKtQFBnBBhEpjhEq4TUYIMRS3gsRjAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}}),
    #"Promoted Headers" = Table.PromoteHeaders(#"Changed Type", [PromoteAllScalars=true]),
    #"Changed Type1" = Table.TransformColumnTypes(#"Promoted Headers",{{"IdBuilding", Int64.Type}, {"SingleType", type text}, {"Price", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type1", "Custom", each let thisid = [IdBuilding] in List.First(Table.SelectRows(#"Changed Type1", each [IdBuilding] = thisid)[SingleType]), type text)

in
    #"Added Custom"

Regards,

Pat