A Time Capsule is helpful to back up multiple computers without trying; your MBP and Mac mini could back up to the TC wirelessly and in the background without having you think about it. I use a TC at home between our MBP and MacBook and it does a great job.
Using a VPN doesn't delete data.
MacBook Pro (15-inch, Mid 2012) 2.3 GHz Core i7, 8GB, 256GB M4 SSD
iPhone 6 - 64GB S/G • Sound System Audio Engine A2 • Display UltraSharp U2412M 24"
Custom Built Gaming PC Skylake Edition | 16GB DDR4 | GTX 970 4G