UI design: Selecting pre-filled max value or a part of it

I have pre-filled available displayed in tables data such as:

1   [80.00]   [Input design here: Select whole row (default) or part of part of 80.90]

2   [4.65]    [Input design here: Select whole row (default) or part of part of 4.65]

3   [13.00]   [Input design here: Select whole row (default) or part of part of 13.00]

4   [13.00]   [Input design here: Select whole row (default) or part of part of 13.00]

5   [14.60]   [Input design here: Select whole row (default) or part of part of 14.60]

(...up to tens of rows)

              [Auto-sum calculation at the end of the rows]

From this row-presented data I wish end user to select whole row (i.e. max) to be used or a custom value such as [30.50] / [80.00] (example).

How would you implement this in UI design? What considerations should I make from the interaction perspective?

TLDR:

How to get user input for partial numerical selection where max is default.

Here's what I am considering (MVP design with existing components):