Sole props are the cheapest, simplest tax structure around.
I don't know why you think it costs "hundreds of dollars to file." Perhaps you're talking accountant's fees? My tax accountant does the Schedule C for about $75 extra as part of our personal taxes annually -- I just provide him with a P&L statement for the year. For previous businesses I did all the taxes myself: the IRS provides lots of easy to understand, free publications for small business. Hell, I did a few years of 1065 (Partnership) returns (stupid decision to form business as partnership!) myself and those are awful.
I agree with your point that sole props are cheap and simple. My comment was within the context of the submission. The author recommended creating a "placeholder" entity to be able to pass years-in-business requirement, and unfortunately, for situations where that requirement exists in the first place, a sole proprietorship is not going to fly.
And yes, I meant accountant's fees. You don't just have your IRS filings, you also have the state and the city which depending on your location require multiple filings plus UBT and other complications. So you have a minimum of 15 different filings (1 yearly plus 4 quarterly, times 3 for federal, state and city), and usually more. I am not sure where you live - personally, I've filed in the US, East and West coast and Midwest and it's never cost me anywhere near $75. Perhaps you and your accountant have been ignoring deductions, self-employment taxes, UBT, etc. I simply don't see how you could have a professional CPA charge $75 for all that.
As far DIY tax prep I think it's a waste of your time to understand all the complexities. Tax requirements change every year and sometimes mid-year... if you are a consultant, your time is best spent doing what you know.
(So did I understand correctly that your accountant files just one yearly form in addition to your personal taxes? That doesn't sound right. If you are not in the US, you can probably gamble on not being audited, otherwise I'd be looking for a new accountant asap, and paying him to re-file your previous years as well).
I don't know why you think it costs "hundreds of dollars to file." Perhaps you're talking accountant's fees? My tax accountant does the Schedule C for about $75 extra as part of our personal taxes annually -- I just provide him with a P&L statement for the year. For previous businesses I did all the taxes myself: the IRS provides lots of easy to understand, free publications for small business. Hell, I did a few years of 1065 (Partnership) returns (stupid decision to form business as partnership!) myself and those are awful.