Once again, since gas dr never provides this caveat:
If you are counting on this treatment, call your local infusion centers as well as your doctor now (before you get sick) and make sure that you qualify for this treatment. There are age and risk factor criteria to qualify.
Once again, in my region it is easily obtained. Please understand that it is well liberalized where I practice.
However, for those in states that are not nearly as forward thinking — you are correct, up front arrangements are probably a good thing.