We've been using a Microsoft Access database for years. I'd love to go to a cloud-based system, but internet is really spotty where we are and we need to be able to access our data, so it's just not feasible for us. The cost is whatever Microsoft Office costs, but much of the time it comes bundled with a new computer/OS. The only think that might be an obstacle is you'll need someone who knows or is able to learn Access, since it can be a little complicated for first-time users.
We also use RescueGroups.org (which is free) to list our pets online, and it acts as a sort of secondary database for us, as it allows you to store a lot of information that isn't publicly viewable but is valuable to the organization.
#DataandTechnology