There is a 7-day free trial version of Lightroom, but there's no version that's free for long-term use. However, if you're a student or work at an educational institution, there are discounted education versions that can make a substantial difference in cost. There are also different bundles of Adobe Creative Cloud so that you can focus on apps that are relevant to your work and therefore limit costs that way (more limited plans are naturally less expensive than more plans with more apps).