A demand loan of $$3000\mathrm{.}00$ is repaid by payments of $$1000\mathrm{.}00$ after two years, $$1000\mathrm{.}00$ after four years, and a final payment after seven years. Interest is $6\%$ compounded quarterly for the first two years, $7\%$ compounded semi$-$annually for the next two years, and $7\%$ compounded quarterly thereafter. What is the size of the final payment?

The final payment is $