If my final k1 has uncaptured section 1250 gain and net section 1231 gain, should I assume these entries account for my share of the cost basis?

Do you have anything on either line 8 or 9 of your K-1?
Just trying to understand the K-1 before I respond.

In box 9c I have a figure for unrecaptured 1250 gain. Nothing in box 8.

Thank you so much for your help.  Regarding section L, I had a beginning capital account of -6230, the current year increase was 28503 and the withdrawals and distributions line reflects -21344 resulting in an ending capital account of 929.  Should I use the 21344 as the final distribution and, as an aside, what should happen with the 929 ending capital account?

One other question, TT asks for the ordinary gain and the 1250 gain.  Should I use the information in Box 9c (Unrecaptured 1250 gain) for the 1250 gain question and the information in Box 10 (Net 1231 gain) as the ordinary gain?

I will start with your second set of questions first:
1) TT will ask you what boxes on the K-1 have numbers in them.  Entering the box 10 amount here is all you have to do.  This figure represents the pass-through gain as a result of a sale of assets at the partnership level.
2) Your K-1 does not provide you with any ordinary gain, so if you are asked that question it is zero
3) Once again, if you respond to the questions asked by TT, you will enter box 9c at that point.  This is also not ordinary gain.

First set of questions:
1) When asked by TT about the sale, you can use the method I described below which will provide you with the $929 of capital loss.
2) Alternatively, you can reflect the $21,344 as the sales price (your distribution) and then reflect $22,273 as your basis which will arrive at the same $929 capital loss.
3) Your response indicates a negative $6,230 as beginning tax capital.  This would indicate to me that you should probably have suspended losses for this amount.  If you do, then this would change the presentation as those losses should be freed up upon this complete disposition.

Thank you for your kind help.

Welcome

ok.  Hard to be certain in matters such as this, but this is what I think or you should check on:

• If you received any final distribution, this amount was included in Section L on the appropriate line.  This number should be actual distributions.
• I assume that you have not maintained your own basis schedule.  As such, we will need to rely on what is provided on the K-1 since "tax basis" box is checked.
• Since tax basis is marked on the K-1, all your partnership activity for the current year is (should) be appropriately reflected in Section L.
• If the distribution figure as discussed above is actual, then we will use the ending balance in determining your overall loss.
• Since there is a balance remaining, this means you have a capital loss on this investment.  The easiest way to reflect this on TT is to enter the following on the applicable form 8949 or questions related to the sale of the partnership interest:
• Sales Price - zero
• Basis - what ever the ending balance is on your Section L of the K-1
• If you don't know the exact date of the disposition, just use 12/31/2017
• The Section 1250 unrecaptured gain will only come into play if you other capital gains on this years tax return.  This may increase your capital gain tax rate to 25%

So what happens in the scenario where my partnership did not end (Final K-1 box is not checked) but the partnership sold the property?
there are amounts in boxes 9c, 10 and 19A.
How do I answer TT preliminary questions of "Disposed of entire interest in the partnership" or "Partnership ended"? Seem like neither of those questions apply in my situation.

Then you did not dispose of the interest and based on your facts, it does not appear that the partnership has completely liquidated.  Once that occurs, you will get a K-1 that indicates it is "final".
You ignore those questions as they are not applicable at this point.

if I did that the "Prior year unallowed passive losses" doesn't gets applied against the capital gain even though the sole partnership asset was sold?

Why was the partnership K-1 not marked final?
Will 2018 be the final year?

yes 8= -136  9= 100%

Nothing on either one.

No.