I have a vps, installed Porto theme on Magento 2, I paid the theme developers for support.
Every time I face theme installation problem, or things like that, I contact the support.
They keep saying the same thing "Please give me FTP access and I'll check that for you."
I reply: "Are you sure you don't want SSH access?"
They don't reply, they don't seem to need it and they don't seem to know much about Linux either, I asked them to give me their public key so I can put it on the server, didn't reply and insisted on ftp access. Porto is the most popular and most well reviewed Magento theme of all time, and their support team is respected.
I'm just thinking about it, what can you do with FTP access? You cannot install a theme, you still need to run commands using ssh, you cannot even check to see if the file permissions are correct.
If given nothing but FTP access, is there anything you can do?