Thank you for sharing your experience.
In fact, most sites that I plan to host are mine, as well as those of a few old and faithful clients.
So, I have no need for one website per server, but only one server with multiple websites and databases.
Basically, a multi sites shared hosting does the job, but I would appreciate more freedom, especially the ability to choose which PostgreSQL version to install, as well as the possibility to install non-web softwares.
Hence the VPS.
Most of my customers have casual edition needs and most of them only use the MODx editor and have no idea about phpMyAdmin and such tools.
However it's perfect if they can have a more limited access like the one you mentioned for CentOS Web Panel, for instance to set an autoresponder when they go on holiday.
Although I'm familiar with CentOS/Debian/Ubuntu and other distros, I hoped using Debian rather than CentOS, as it's easier to find recent binaries, also for non web softwares.
For Debian, I read good things about Ajenti and DTC (Domain Technology Control).
Can someone compare them?
The company currently hosting my websites, uses some panel which looks like an enriched AlternC, maybe home made. Although the interface is a bit outfashioned, I like it as I'm familiar to it. (I add a screenshot as attachement.)
I like the look of AlternC (http://alternc.com/Home-en
To login in the demonstration site: demo / demo )
but I think it's a small (one man?) project and maybe no more active.
I would fear a too small community if going with AlternC.
For CentOS, I read good things about Kloxo-MR and DTC (Domain Technology Control).
The CentOS Web Panel (CWP) that vigilante
mentioned looks great too and I must have a closer look to it.
I see it allows automated backups, which is great.
I also head good things about Webuzo as very easy to use.
It has both free and paid versions.
To be honnest, I've never been a big fan of CPanel, although I know it only as customer from shared hosting plans.
In general, I like when the interface is well structured and does not display a ton of icons.
For the VPS, I was planning going with VULTR (and I'm still), as they are of the very few ones offering a 5$/month plan, and with more RAM (768 MB) than competitors. They have servers in Europe, which is good in my case. The small SSD will suffice my needs.
As you mentioned, VULTR has interesting features (ISO upload, a.s.o.).
From what I read DigitalOcean is renowed for its tutorials, but I may inpire me from them on a VULTR plan, especially when choosing an "apt" distro.
I planed using Debian rather than Ubuntu, as for a server, but I must admit that the free panels available for CentOS may make me change my mind.
To come back to my main question:
How much time consuming is hosting ones own websites (and possibly those of a few clients) on a VPS?
My main issue is not the initial setup, but the maintenance for security upgrades.
When not doing it on a daily basis, I asssume that one forgets some things.
How much time per week or per month appears you necessary for this task?