How to Get Top 1 sales for today

If you want to perform this filter in Power Query, here is how you can do it.

First, filter the date column for values equaling today.  Then filter the total column for the max value.

BEFORE

AFTER

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcioyMFTSUQIThgZAwgiEDcBCukZAZGBkpBSrA1ZohKLQGITRFcYCAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [branch = _t, ItemId = _t, price = _t, Qty = _t, Total = _t, Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"branch", type text}, {"ItemId", Int64.Type}, {"price", Int64.Type}, {"Qty", Int64.Type}, {"Total", Int64.Type}, {"Date", type date}}),
    FilterForToday = Table.SelectRows(#"Changed Type", each Date.IsInCurrentDay([Date])),
    FilterForMax = Table.SelectRows(FilterForToday, let MaxValue = List.Max(FilterForToday[Total]) in each [Total] = MaxValue)
in
    FilterForMax