I'd be hesitant to say it's an average, because I just don't know. Two to three thousand seems to be a common number for including an airplane on the certificate.
That doesn't include providing anything, however. That's simply to list the aircraft on the certificate. Additional fees may apply for training the crewmembers provided by the owner, etc.
If someone wants to put an airplane on your certificate and have you fly it, it becomes more of a dry lease arrangement on your part; no owner will pay you to use their airpalne and fly it. I think here we're talking about a situation in which a company doesn't have authorization for a specific aircraft type under their own certificate (or perhaps they don't have a certificate),and they want it on yours. In such a case, they typically provide the pilots, maintenance, etc.
To do this, they need their maintenance approved under your program; there are certain costs associated with this, and they'll vary with the type of maintenance program, the type of work required, the aircraft, etc.
The crew must be trained under your certificate and must have checkrides and currency under your certificate, and must abide by your operations specifications. Your certificate will need approval to operate that aircraft. Generally when this kind of arrangement is made, it's done when you already hold this authorization; that's why the interested party is coming to you in the first place.
The interested party should be paying for the cost of training the crewmembers, the checkrides, etc. The 2,000 dollar fee is for the privilege of using your name, and operating under your certificate. The amount will vary according to the type of operation and aircraft involved, of course. A two grand fee to operate a Cessna 172 might be a bit much, but might be quite appropriate for a light jet.
Essentially, the two grand is for your liability and for your good name. The aircraft being operated in this manner is being operated as one of your company aircraft, and accordingly you can only extend yourself as far as you are comfortable. A couple hundred dollars wouldn't make me very comfortable. Having said that, even if the management fee is five thousand, you still need to recognize that you hold operational control over this aircraft. You may not be paying the pilot wages, or you might. It doesn't matter; it's still you that holds operational control...and that's a lot of weight for a few hundred dollars.
Additionally, you become responsible for managing maintenance personnel and flight personnel on a drug program, and you are responsible for the facilities and practices to be used at the operating location for this aircraft. Again, all expenses to you, and liabilities...as well as adherence to all practices, operations specifications, etc. This can be a bit of a sticky position. The operator of the other aircraft is sometimes likely to feel autonomous, and feel as though they've paid for the privilege to do so, when it's not the case. If you both get on well together, then fine, but if not...it can provide for a sticky environment in which to work.
If the jet provider can really find someone to manage their airplane for two hundred dollars, let it go. You can't compete with such a ridiculous amount. However, I surmise that this person is going far overboard in trying to lowball you; not a good sign of things to come. Getting aircraft to put on your certificate is easy; getting good partners isn't. If this person is pulling this before you're even connected financially, I'd flush them. My opinion only.
