I can't say with absolute certainty that my books are 100% typo-free.
But I can say pretty confidently that they are the same quality, in terms of typos/spelling/grammar at least, as books published by big-name houses (which also tend to not be 100% typo-free).
I can understand relegating copyediting and proofreading budgets to a low priority if you have experience in that and the time to go through thoroughly. But what about content editing? It's harder to spot things like telling where you should be showing, weak characterisation or a logical leap in a plotline because you know the material too well to see it objectively. What would your stance be on content editing?