This can be true. Depending on your schedule as well as consistency with the bunny, they can be very easy to care for and do not smell. The only really smelly things for a rabbit are the hay, and their urine. Bunnies can be litter box trained, which helps with both care and the smell. If the litter box is maintained and cleaned on a daily basis there should not be a smell. This is also dependent on the litter used. If placed on a schedule, your life will begin to revolve around the schedule and become second nature caring for your rabbit.
Litter Box training your Bunny
Bunnies are naturally clean animals, they will bathe themselves and also designate a "bathroom" in their enclosure. They are very similar to a cat in that respect.
Using a cat litter pan, a shorter litter box is easiest for the bunnies to get in and out of, using the paper pellet litter the bunnies will usually hop in and out of their litter box to use it. We also place hay In the litter box as many rabbits like the litter boxes to hang out in as well.
We do not recommend any "Pine" litter as this can cause respiratory allergies to bunnies.