Not being in a community property state, you don't have the option of splitting things between two SCH C's on your joint tax return. Understand I may use "partnership" and "multi-member LLC" interchangeably here. For the purposes of this thread, the only difference is the spelling. Literally!
First, on the 1040 joint return you will show that the sole proprietorship was "closed, sold or otherwise disposed of" on Sept 30, 2018. (Oct 1st is the first day of the fourth quarter, and you don't want to have to deal with quarterly taxes on the sole prorietorship for just one day of the 4th quarter.)
Then you will show that all assets (depreciated or not) were "removed for personal use" on Sept 30, 2018. If you show anything other than removed for personal use, then you will asked for a sales price for the asset(s), and you did not sell them. The same holds true that you will show all inventory "removed for personal use" on Sept 30, 2018.
Of course, you will show all income and expenses for the business, up to Sept 30 2018 too. When done working everything through the SCH C and the SCH C is done, you'll need to print out the 4562's (both of them) for the business assets. You will need these for the partnership return. You will also need to know the exact amount that *you* paid for all the inventory removed from the sole proprietorship for personal use.
Understand that once all this is done, then and only then, can you start your first IRS Form 1065 Partnership return.
Now I sincerely hope you are using the CD/Desktop version of TurboTax 2018. All that you need to do can be (and will be) a real PITA with the online version. I don't use the online version. So I'm not that much help with navigation issues like I am with the CD/Desktop version of the program.
So get the above done and we'll go from there. You will have some math to do when entering/transferring your assets and inventory to the 1065 in TurboTax Business. It's really easy; but it's just as easy to do the math wrong and screw things up too. So that's why I"m taking this one step at a time. So close the SCH C business first per the above guidance, and once you have both 4562's printed we'll go from there.
Both 4562's print in landscape format. One is titled "Depreciation & Amortization Report" and the other is titled "Alternative Minimum Tax Depreciation".
