Bonnie,

Many lawn tractors come with this feature. Mine has a "mulch plug" which
blocks the grass outlet, resulting in the leaves being chopped to a semi
dust consistency. I bet you can pick such a tractor up for much less than
$500 second hand. I have several acres to mow and find the tractor to work
quite nicely on the lawn. In the Fall I allow the leaves to fall and then
pick a dry day to mulch. Mulching is best done using the tractor in one of
the slower speeds. I think you'll be very pleased with the result and if you
aren't sell the tractor next Spring and you'll get most of your money back.

Good luck,
Dave M.