You almost certainly won't, but if you wanted to, what are your options? Having liked the B747 since whenever, I focus there. Go new, and get a freighter for 280 $ Millions or a seat-in pax version for 340$M. Approximate prices just to set the stage. Just now there are 3 such birds sadly abandoned as below: 'Last call for owner of 3 abandoned planes': Malaysia Airports seeks owner of Boeing 747s left at KLIA, SE Asia News & Top Stories - The Straits Times These are Unit Serial# Line# Type TF-ARH 22669 549 747-230BF TF-ARM 22363 490 747-230B(M) TF-ARM 22382 498 747-2F6B All were last flown about 5 years ago, by Air Atlanta Icelandic. Units have been in situ for 5 years, so we might assume that registered owner has lost interest in paying ever-increasing storage charges. Else they would have done so, long ago. Let us suppose for convenience that the payment due would be 10 million $US per unit. Can they fly out now? Absolutely not! After 5 years, engines and other systems need to be refreshed. Let us suppose for convenience that would represent 20 million $US per unit. That large number is based on their remote Malaysian location relative to the Boeing-fixer-uppers you’d be employing. Are they ready for your use now? Not if you want them fitted with nice new interiors. So throw another 10 million $US at that. While none of the above costs are strongly tethered to reality; that is the job of your staff. But they are not goofy underestimates. A big bird for 40 instead of 300 sounds like a tasty treat, just in case you happen to be in the market. Ah, to dream.
100 gallons per mile in cruise would be about as good as it gets. How 'bout an Air Force One paint scheme? Too conspicuous?
I would expect that, if you tried to paint a "VC-25A clone", then you may expect to be visited sometime in the future by some VERY humorless US.gov folks.