If 3rd July transaction is paid off then, what will be the total value of assets? If owner invested additional K500 then which two elements or side will be affected?

The liability to ABC Furniture is K1 700.

Paying off the liability means cash will decrease.
Original Cash at Bank = K3 500
Payment = K1 700
New Cash at Bank = K3 500 - K1 700 = K1 800

Assets include Cash at Bank and Inventories.
New Total Assets = New Cash at Bank + Inventories
New Total Assets = K1 800 + K1 500 = K3 300

The total value of assets will be $\boxed{\text{K3 300}}$.