a short summary which could be an oversimplification because we can't see the k-1
look at schedule L beginning capital
that's supposed to be your beginning tax basis
then look at the line that says current income or (loss) note that any amount on 9c is included in line 10 (9c is how a portion of line 10 is taxed),
the sum of the two lines, assuming no amount is on capital contributed during year (you would then add this amount in)
or other increase(decrease) - if not zero, the effect on your tax basis unknown - the partnership would have to provide you with that info
if the partnership was liquidated and no proceeds were received other than distributions on line 19. then line 19 becomes your sales price. you do not reduce basis for this.
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as an alternative you can reduce basis by the line 19 distributions
then use sales price of zero
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if this is not a publicly traded partnership and you received proceeds that were not distributions most likely they would add to sales price.
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however, if this was publicly traded partnership the reporting is completely different. you should have been furnished with a sales schedule to determine proper reporting
