"We got a cheap deal at first, but then had to pay for a lot of expensive customisations before we could use the CRM properly."
We’ve heard this from multiple clients: you may not pay much to begin with, but then you find that many of the more charity-specific features you need are available only as expensive add-ons.
If free licences are offered, these are likely to be read-only or have minimal functionality. In some cases, people found they had to pay to add bespoke features to each licence before they could use them in the way they wanted.
Contrast this with Charitylog, where there are no hidden costs and you get unlimited user licences with the standard plan.