Stay far far away from any charter operator. They will promise you the world and stuff only their pockets! They will want to put your airplane on their operating certificate and use and ABUSE your asset for only their gain! Don't buy into "we buy fuel at volume discounts unavailable to Part 91 owners" With fuel programs such as CAA (Corporate Aircraft Assoc) supplying fuel at or better than national contracts!
A properly set up Part 91 flight department can and will have all the tax benefits of a for hire operation. Pay a little up fromt for years of savings!

Charter is down significanly, people are offering the aircraft for charter below cost. Many have or are about to go out of business. Pilot turnover is significant with you paying for the training. Insurance is more expensive and their safety record is 13 times (per NBAA stats at NBAA.org) worse than a professionally flow "not for hire" operation.
If you cannot make the numbers work without charter stay away from ownership! (Even more so in these incertain times!)
Hire the right Chief Pilot and you will be set up for many years of success!