Leasing a commercial truck gives you the right to use it as you wish, for the period the lease lasts. Naturally, there are also certain conditions. The person leasing you the vehicle is responsible for maintenance and repairs, but not if it was your neglect or misuse that caused the damage. You will be required to make monthly payments, same as if you were renting an apartment.
If you need a commercial truck for your business, leasing is a very good option, especially if you cannot afford to pay a big sum of money upfront. Considering that you will not pay for the cost of the vehicle, the commercial truck leasing monthly payments may be even lower than a loan, which makes the lease affordable, especially if you compare it with the utility of the truck for your business.
Leasing is good because it allows you to avoid debt and, once the lease agreement comes to an end, you can choose to upgrade to a better vehicle. On the other hand, you also have the option to purchase the truck at the end of the lease, for its residual value (which is determined in the original leasing contract).
Loaning a commercial truck is not so great, mainly because it is not an investment; you are just using someone else`s vehicle. There will be higher monthly payments and you will likely be required to purchase extra insurance.