That is how TT works. I enter an IRA amount and bottom line (Fed and State) changes. Also it considers all tax deductions.
Since my situation is a little unusual, I decided to take your suggestion and give TT a try.
I will tell you that if one is trying to get a rough idea, the spreadsheet is BY FAR faster than TT.
TT treats this as an actual return, and doesn't let you override or force anything. So for example unless I enter a SSN for all my 10 dependents, it won't count them for Child Tax Credit.
But the biggest issue with TT for me at this point is that:
And since I have an outsized deduction there, I cannot even get close to my situation without being able to enter that information. Contrast this with the Spreadsheet which is available as a draft. And even though certain parts aren't yet ready (such as form 1099), I am able to compensate for that by entering information in other areas, and overriding certain entries. Whereas I couldn't figure out anywhere that I might enter the deductible amount that I expect to be reported on my form 1098.
OTOH, I will admit that TT seems a lot more detailed and thorough, almost to the extent that I'm thinking of ditching my CPA for the personal returns, and just letting him to my corporate returns.
