Shifting formulated cells based on value of a certain cell

[BKGLTS]

Hello,

I need help with the following please.

In row 1 I have a row of currency values, A1 thru A1000.
In row 2 I need a formula for each cell B1 thru B? that multiplies its corresponding number in row 1 by a factor (B4), but also looks at A3 to tell it how many cells to the right to shift.

Ex:

A1=$1 A2=$2 A3=$3
B2=$1.5 B3=$3 B4=$4.5
B3=1
B4=1.5

One way to think of it is the formula in B1 multiplies the value in A1 by the value in B4 and then shifts to the right by the number of columns in B3.
This is the same for all cells in row B basically so the numbers can shift as far as they need to the right.
B3 will be manually changed frequently to look at different results.

Thank you!
B

 

[BKGLTS]

ok thinking of doing this in reverse with hlookup.

 

[BKGLTS]

Nope it is beyond me.
I was thinking the formula in the Row 2 cells would basically say look in the A1:A1000 range and find the cell that is B3 number of columns behind it and multiply whatever the value is in that cell by B4. And if it errors out put nothing "".
I am thinking maybe some sort of Index Match Search formula.

Still need help please.

Thank you,
B

 

[BKGLTS]

I was able to get it to work pretty well with an OFFSET function. Not the most elegant because it interferes with other surrounding data which forced me to reformat the sheet, but still works.