I have two major problems with any lease purchase program.
1) you can only get a truck that is spec'd like most any other fleet type truck. That isn't always a bad thing, but there is no tailoring the truck in terms of engine, trans, diffs, types of hubs, customizing the interior to what you want, and a myriad of other things that make it a truck that actually is more suited to what you are trying to accomplish.
2) Negotiation. There really is no negotiating deals with a lease purchase. You are in for what they think the vehicle is worth, which is always more than what it truly is.
When I can spec a truck that will carry 2000 lb more than any of the carrier's fleet trucks, and have axles and suspension spec's that maximize tire and component life, the sleeper set up with exactly the types of compartments/closets that meet my needs, several frame rail storage boxes, complete with a 500 hp motor with 18 speed trans, complete frame and suspension sealing and painting to enhance corrosion protection, even body matched painted fuel tanks, and details right down to the best Conmet axle hubs, a Xantrex inverter/charger, full lockers in the drive axles, etc, and do it for a total cost that can be negotiated to make it a manageable purchase that is easily comparable and many times less than any of the fleet type spec lease purchase stuff. That is the only way to go.
And doing a glider is not going to generally be a lease purchase thing. Fleets really haven't figured out that these things exist. But that is what I did, and I have no regrets. There is absolutely no way I would buy one of the new emission laden trucks nowadays.