If the Qataris want to give the Pentagon a $400M plane, then I'm ok with that. As we then have to spend a few hundred million to make it operational as a replacement or alternative to AF1, I'm probably ok with that.
However, if Trump is going to bequeath the plane to his library, which would allow him to then use it as a private citizen after he has left office, then I'm not OK with that. If he, or his "library", wants to reimburse us for the money spent, and for the money that will then need to be spent to take out all the tech etc. that we put into the plane, then sure, plus obv. the fair market price of the plane. When all is said and done, it's probably around the $1B mark ($400M + outfit it for AF1 + de-outfit from being AF1) that the Trump library should cut a check for, payable to US gov, aka US taxpayers. In that circumstance, I'd be OK with his "library" having it.
It brings a new meaning to the mobile library business!