Get the details of the lease and post them here. The price of the truck the lease is based off. The percentage rate of the sales tax on lease payments, residual amount. My current truck is a lease, but I walked into it fully intending to buy it out at end of lease. Which I just sent off my buyout check to Chrysler Capital last week. I was paying $403/mo on my 2020 Built to Serve with 12k year mileage. Residual amount was $28,800. Unfortunately interest rates went way up during the lease period(thanks Bidenomics) so my buyout payments are higher than the lease payments. But I saved $1000 on sales tax overall vs financing the full amount up front.
In Nebraska sales tax on vehicles is paid during registration and can't be financed into loan. Unless you lease, then there is a sales tax on the monthly lease payments, and you don't pay sales tax at DMV until you finance the residual.
As for lease end options. You can either just turn in the lease losing all your equity left in vehicle, which in our trucks is quite a bit. Then your lease turn in goes to auction where it is usually sold for a fraction of actual value.
You can negotiate with dealership to work it as a trade in, where they buy out the lease and give you some of the equity towards a new vehicle. That allows them to keep the truck as dealer inventory and you get to use the equity. Win/win for both parties. But this option will never be told to you. You have to know about it and request it.
Or you can just buy it out yourself and keep the truck. Don't believe the Chrysler Capital website, you do not have to go through dealer to buy out the vehicle. This is a tactic to get you back into the dealership to have them try to sell you a new vehicle. You can secure your own financing and just mail the check directly to Chrysler Capital along with odometer disclosure.