For those that file with the IRS, it is not really that big of a deal to actually work directly with the IRS. I, self employed, nearly had my own coffee cup & a 1st name basis with them. For a while I think they almost recognized my voice when I called .... glad those days are over.
I think.
Even *they* discourage working with the 3rd party offerings because of the scam potential. The exceptions for paying less tax that an audit or just being behind are not that difficult to find out about and they will tell you when asked ... but you must ask as they will not usually offer. AND they don't offer because THAT is usually in some other division. This is the government after all.