I've got 100+ accounts. There are a few things to keep in mind.
First of all, can your Internet connection handle that much traffic? Aside from dedicated power, that's probably the biggest advantage of a VPS. I don't know where you're at, but if you've got some crappy 10x2 cable service, you aren't going to have a good time.
Secondly, I've done it - but running something like MP on a consumer OS (and you're only going to get Win 10 now) is a PITA.
If you want to buy something, I'd suggest you go over to dell.com & configure an entry level server.
At least quad core - I've got 8 cores
RAID (I'd probably just go RAID1 since you'll only need 2 drives)
Server 2012 R2
UPS backup power