Porter's weekly earning is $8x5 = $<<8*5=40>>40.
Porter's monthly earning is $40x4= $<<40*4=160>>160.
The extra amount he will earn when he works on his overtime is $8 x 50/100 = $<<8*50/100=4>>4.
So the amount he will earn on his overtime is $8 + $4 = $<<8+4=12>>12.
Since he will render overtime once every week, the total overtime pay he will earn in a month is $12 x 4 = $<<12*4=48>>48.
Therefore the total money he will earn in a week is $160+$48 = $<<160+48=208>>208.
#### 208