Tara has to make a $1000 x 20/100 = $<<1000*20/100=200>>200 down payment.
Since Tara wants to pay $20 more for the down payment, her total down payment will be $200 + $20 = $<<200+20=220>>220.
So her remaining balance payable over a year is $1000 - $220 = $<<1000-220=780>>780.
Tara has to make a monthly payment of $780/year / 12 months/year = $<<780/12=65>>65/month.
The total cost of her payments for 4 months is $65/month x 4 months = $<<65*4=260>>260.
Therefore, Tara's balance after 4 months is $780 - $260 = $<<780-260=520>>520.
#### 520