Which LMS do you use and why?

I’ve been training for about 20 years writing courses for about 4 years (ish) and Storyline for about a month - and I have to say I’m delighted with it. Anyway I’m in the process of setting up my own business and I have been commissioned by one company to write 5, maybe more, courses and be paid an annual retainer to keep them up to date and make any requested amendments. So the basic deal is, I write them and they host them on their own server. All well and good.

However other potential customers would like me to host the courses on my own website rather than their servers and, via an LMS, allow their staff to access them. So the structure would be:

I host all the courses on my website.

I have an LMS on my site with different users and administrators.

So if my first customer decides they want me to host the 5 courses they have around 4,000 staff all of whom would need registering.

Let’s say my next customer wants the same. So now I need to host 2 entirely different customers each with (for example) 4,000 staff (i.e. 8,000 users).

And so it goes on. Customers will want to be able to monitor what their staff do and get reports/statistics, etc.

Many companies selling e-learning on an annual licence basis offer this service. Can I set this up with any LMS that’s out there or am I biting off more than I can chew? Bearing in mind I’m just starting up, the sort of thing I’m looking for might require me to sell my house to fund it.

I do hope this makes some kind of sense.

Tony