how to deal with Invoice after Down Payment

HI ,

I am testing Down payment  for vendor and We have  activated withholding tax in our company code . I was just wonder how system will behave if we have suppose 50 % of down payment   .

Complete  process is as below

Create a request in F-47 for 50 % of Invoice before Invoice comes

then Run f110 and paid to vendor

Now after this Invoice will come and get posted .

Now I have some concerns

1) I have set up  Tax  codes on payment and enter in f-47 can see tax amount is deducted  there .

2 ) How invoice will be processed  whether we will deduct whole Wh.Tax  or need to set up .

3 how we will deal with rest 50% of payment

Many Thanks