Yes, both GitLab and CircleCI offer a Free Trial.
GitLab is designed for Large Enterprises, Medium Business and Small Business.
CircleCI is designed for Large Enterprises, Medium Business and Small Business.
Pricing for GitLab Starts at $19/User/Month whereas for CircleCI Starts at $39/Month.
Some top alternatives to GitLab includes Codeship, Semaphore, CircleCI, Bamboo, AutoRABIT CI, Buildkite, CloudBees Core, Travis CI and Bitbucket.
Some top alternatives to CircleCI includes Codeship, Semaphore, GitLab, Bamboo, AutoRABIT CI, Buildkite, CloudBees Core, Travis CI, AppVeyor and Bitbucket.