OpenCart on PaaS

I would like to put one or more OpenCart ecommerce on a self-installed PaaS.
Some questions:

1) is possible to move all 'uploaded' files to an external object storage? This because almost every PaaS has ephimeral storage

2) based on point 1, the project must be horizontally scalable, by adding 2 or more VPS with OpenCart installed pointing to the same database. Any locally uploaded file won't be available to the other VPSs, thus there is a need to upload everything to an external storage (maybe Amazon S3 or similiar)

3) updates: is possible to do a totally unattended updates? Something like a script to run from command line to automatically update the shop

Yes, We can move all 'uploaded' files to an external object storage in a opencart site.