Thankfully, Westlaw alerts you when you are about to be charged for accessing documents outside of your plan. You are then given the option to click through and incur the charge or exit. Last year, I was up against a deadline and I needed some information relating to a UCC Article 9 sale, my client authorized the charges and I wound up spending close to $200 in about 15 minutes.
Over the past couple of weeks, there have been two or three occasions where I needed to access bankruptcy cases and other federal cases outside of our subscription. I found everything I needed on Google Scholar for free in about 30 seconds.
To find caselaw on Google, go to Google Scholar. There will be two choices directly beneath the search box. One is for articles and the other is for legal opinions and journals. Click legal opinions and journals and search away.
I haven't tried any searches just based on search terms, so I don't know how well that works. I always have the citation. This is a really convenient service when a case has been cited to you, and you want to grab a copy of it for free.
I don't think I would rely on Google for all of my research, however, because it doesn't Shepardize cases.