The thing with car fax is it may catch some things, but lots of others it will miss. I think it gives a false sense of security. There is likely, but not certain, that there is an issue, but I feel no confidence when it says it is clean. So you can perhaps weed cars out by it, but you don't get much to go by with a positive report other than knowing they did not happen to find anything, not that there was nothing to find. And I have read of too many false negatives to really even trust that it is accurate enough to bother with.