A demand loan of $$$$6000\mathrm{.}00$ is repaid by payments of $$$$3000\mathrm{.}00$ after two $$years$,$$$3000\mathrm{.}00$ after four $$years$,$ and a final payment after six years. Interest is $8\%$ compounded monthly for the first two $$years$,9\%$ compounded semi dash annually for the next two $$years$,$ and $9\%$ compounded annually thereafter. What is the size of the final$$ payment?