A new smartphone is often expensive, especially if you purchase it without a contract. Most phone plans offer the option of leasing a phone.
This is connected with my question awhile ago. I charge my phone at night and it is a new phone. Maybe I should buy not that expensive phone as a back up?
It is up to you. Since it will be your back up phone for your work, yes you should buy to avoid damaging your new phone. As long as it can install apps and files for your work.