Yes, both GitLab and Buildkite offer a Free Trial.
GitLab is designed for Large Enterprises, Medium Business and Small Business.
Buildkite is designed for Large Enterprises, Medium Business and Small Business.
Pricing for GitLab Starts at $19/User/Month whereas for Buildkite Starts at $2,999/User/Month.
Some top alternatives to GitLab includes Codeship, Semaphore, CircleCI, Bamboo, AutoRABIT CI, Buildkite, CloudBees Core, Travis CI and Bitbucket.
Some top alternatives to Buildkite includes Codeship, GitLab, CircleCI, Bamboo, AutoRABIT CI, CloudBees Core, Travis CI, AppVeyor and Drone.io.