Ben, we have not had success in getting paid for the B12 either. But, do add a 25 modifier to the E&M code. The code you're using for the injection admin is correct.
As for deciding what to charge for your other tests, you might try going to your Medicare carrier website and checking their fee schedule for the particular codes. Then you can decide what percentage you want to apply to that for your commercial payers. Your contract with your commercial payers should indicate what percentage of medicare they pay for labs and drugs. I have heard the rule of thumb that your fee should be 20% higher than your best payer's reimbursement.
Also, with regard to which of the Hospice modifiers to add to your claims, there is a good decision tree on the Trailblazer Health Website. Even though this might not be your medicare carrier, you may still be able to check it out. Good luck with all this!
