Does not require fellowship, things that you will routinely get adequate training for in neurology residency:
Ambulatory EEG
BOTOX® Injections
EEG
Lumbar Puncture
Things you will be trained for in neurology residency, but certainly not at the expertise of a fellow and probably thus will not do once you are an attending. Usually requires neurophysiology fellowship to be creditaled at your hospital's neurophysiology lab and to do in an inpatient setting
Brainstem Auditory Evoked Potential
EMG and Nerve Conduction Studies
Evoked Potentials
Intraoperative Monitoring
Somatosensory Evoked Potential
Vagus Nerve Stimulation
Visual Evoked Potential
Will have adequate training to do some simple studies in your office if you want to, and claim for reimbursement, but would likely not be creditaled to do these at your hospital inpatient or at the hospital run neurophysiology lab
EMG and Nerve Conduction Studies
EEG
Some neurology programs do provide adequate training for the following, and some do not. If they do, then yes, you can do them. If they don't, you can seek the extra training required to do them through CME on your own bill and don't need fellowship
Carotid Ultrasound Examination
Echocardiogram
Definitely requires some extra training beyond neurology residency and very competetive to obtain. Would likely have to do a baseline vascular, critical care, or stroke fellowship prior to receiving training for these. Will compete for training slots with radiologist and neurosurgeons, not easy to obtain
Carotid Artery Blockage
Cerebral Catheterization and Angioplasty
Percutaneous Transluminal Angioplasty and Stenting (PTAS) of Carotid Artery
Usually done by anesthesia
Epidural Blood Patch
Usually done by a surgeon
Nerve and Muscle Biopsy
Most general neurologist don't have to time or desire to do this
Neuropsychological Services
Of course the reimbursement for any procedure is good. There is nothing to stop you from doing say EMG/NCV in your office on patient's without fellowship training and claiming reimbursement. However, if you see an odd finding and have no clue what it is, you'd end up refering the patient to somebody that does have more experience than you and the test would likely be repeated = unhappy patient. Most neurologist are good enough to read an adult EEG without fellowship training and get reimbursement.
Overall, I'd recommend neurophysiology fellowship to do some of the other stuff you mention above to get full credibility at your hosptial on both the inpatient/outpatient side and get reimbursement. Will bolster your salary as a general neurologist and is only a one year fellowship.
People now a days speak of interventional neurology with cerbral angiograms, carotid stenting, and all of that stuff you mention above. I am certain the reimbursements for these is great. However, your training would be lengthy and hours would be similar to that of interventional cardiology. You will not get training for these right out of neurology residency, prior to an interventional fellowship, you'd have to do some fellowship that included neuro critical care patients: stroke, vascular, Neuro ICU, etc. You'd then compete for these fellowships with neurosurgeons and radiologist alike. That's not to say it can't be done, or to discourage you, but just to point out that the training is fairly greuling and lengthy.
Of course, you can always promote yourself as general neurologist doing pain procedures: botox, trigger point injections, prolotherapy, acupuncture, all stuff you can learn how to do by attending CME courses. Get a group of people interested, make a reputation for yourself, and the referals will come to your door.