The holy Grail of vendors

Last night I was vendor hopping when I hit on the best stocked legendary mods vendor I've ever seen. This person had every 1, 2, 3 and 4 star mods I've heard of and then some. And a large number of each. The downside, they were incredibly expensive. The 4 stars where priced between 32K-38K caps. I had enough caps, I just had to decide which mod I should get one of. Then as I was browsing and agonizing, the camp vanished and I feel to the ground. I didn't get a single mod. Will probably never see this vendor again either.