Custom Approval in JDE 8.12

[Rauf]

I am aware about how Approval Route and Distribution List for Purchase Order is working. We have a new requirement that an amount to be assigned to one person and it should be approved by say four managers.
The idea is very simple.
We will enter the amount, for example.

Person          Amount       Project Code
Rauf             100            XYZ

Then we have to define for the project XYZ we need approval from four persons.

Approval Level        Address Number
1                          123
2                          980
3                          580
4                          700

So the data entry finalizes when 700 approves.

Should we make new custom tables or should we can fit it some where in Approval Routes or Distribution list.