Most budgie cages can be scrubbed in the bathtub weekly and the lining paper changed daily. Budgies occasionally succumb to health problems which require veterinary care. Try to find a vet who is experienced in avian medicine since treating birds is quite different from treating mammals. Budgies are tiny and inexpensive pets, so it's easy to think that they are going to be less trouble than some other pets. This is not necessarily so.
Budgies have tiny voices, but when they are happy they chatter almost constantly.
Some people find this pleasing while others are annoyed by it. They aren't the messiest pets you could have, but expect a generous scattering of seed hulls and feathers around the cage that will need regular tending. Don't allow them out with the ceiling fans running, and cover your windows so that they don't break their necks flying headlong into one. Obviously they must be protected from cats, dogs, and little humans who might squeeze too hard or hit and grab at them. Budgies can be wonderful and loving companions throughout their life times.