Multipurpose server in a small organization

Question

Asterisk

Good day)
I work in a small organization, a year ago we were a startup, the profile is not related to IT.
More recently, we had a need to put a server. We cannot allocate too many resources for it, at this stage for sure)
So, we need the server for four purposes:
1) IP-telephony server. Asterisk, it serves mainly to ensure that there is an IVR after hours and for unforeseen situations. Later, the list of duties of the asterisk will expand, and it will be associated with the CRM system.
2) Itself, actually, CRM. It is needed to optimize workflows, 3-5 machines will access it, no more. When there will be more, we will change the server :)
3) I also think to give up hosting and do everything right at hand. Transitions to the site - no more than a thousand per day, no more than 6 in one minute.
4) Organization of a file subnet. Access to it from the outside. The file storage is small, but for moderately important files. Backup documents daily. But what to do with working files (for example, files from the turnover, which are accessed daily for several days, and then they are not relevant) I can’t imagine.
I plan to use the usual desktop solution for the server, there won’t be enough money for the server :(
I climbed the whole toaster, it seems like a decent amount of information cleared up. I didn’t ask a question for a month, but just read it. Now, nevertheless, I decided)
Questions
1) I plan to do everything on Hyper-V, and then everything else on virtual machines. Is it correct, if not, why not?
2) How many virtual machines to create? Should I separate everything completely, or can something be combined?
3) There are doubts about hosting in terms of its resource consumption, nothing more.
Well, in general, if there is a similar experience and you know about something special here, I will be very glad to hear.

Answer 1

1. Asterisk is definitely Linux. If an analog channel card is used (for example, DAHDI), can you throw it into a virtual machine?
2. File storage - Samba on Linux, one resource on Raid for important data and one on a separate screw for junk. Automatic junk removal 20-30 days after creation/last access.
3. Site - depending on the implementation of Linux or Windows.
4. CRM - depending on the implementation of Linux or Windows.
In summary, if Asterisk cannot be transferred to a virtual machine, and the site or CRM work on Windows, then take two servers, otherwise everything is just on one server with Linux without virtualization.

Answer 2

I'm planning a regular desktop solution, I don't have enough money for a server one

- that is, call telepaths to guess how much it will be in money?
PS Do you pay $1000 per month for hosting?