I am as confused as My Answer Is This.
I think you want three drop downs House1, House2, House3 and you want to select items from the list you show in post
#9 . And you want the selected items to be listed below each header, H1, H2, H3. And you want the repair item to be selectable ONLY ONCE.
If all that is true, then do this for a test sheet which will duplicate mine. It is a bit complicated. Use Sheet1 and Sheet2.
On Sheet2:
Copy the list on post
#9 and paste it on sheet2 in columns A, I & Q.
cell B1 enter > =IF(COUNTIF(Sheet1!$B$2:$B$12,A1)>=1,"",ROW())
cell J1 enter > =IF(COUNTIF(Sheet1!$I$2:$I$12,I1)>=1,"",ROW())
cell R1 enter > =IF(COUNTIF(Sheet1!$P$2:$P$12,Q1)>=1,"",ROW())
Pull the three formulas down to the end of the repair items lists
Still on sheet2:
cell C1 enter > =IF(ROW(A1)-ROW(A$1)+1>COUNT(B$1:B$12),"",INDEX(A:A,SMALL(B$1:B$12,1+ROW(A1)-ROW(A$1))))
cell K1 enter > =IF(ROW(I1)-ROW(I$1)+1>COUNT(J$1:J$12),"",INDEX(I:I,SMALL(J$1:J$12,1+ROW(I1)-ROW(I$1))))
cell S1 enter > =IF(ROW(Q1)-ROW(Q$1)+1>COUNT(R$1:R$12),"",INDEX(Q:Q,SMALL(R$1:R$12,1+ROW(Q1)-ROW(Q$1))))
Pull these three formulas down to the end of the repair items lists.
Still on sheet2:
Name the columns C, K, S:
With the mouse, select C1 to C12 > Formula tab > Defined Names > Defined Name > Define Name... > New Name box > Name window > House_1 > Scope window > Workbook > Refers to: > =OFFSET(Sheet2!$C$1,0,0,COUNTA(Sheet2!$C$1:$C$12)-COUNTBLANK(Sheet2!$C$1:$C$12),1) > OK.
Now do the same for the other two columns, K and S with the names House_2 and House_3. Using these last two formulas in the Refers to... window.
(Be sure to use name exactly as shown, with the underscore _.)
=OFFSET(Sheet2!$K$1,0,0,COUNTA(Sheet2!$K$1:$K$12)-COUNTBLANK(Sheet2!$K$1:$K$12),1)
=OFFSET(Sheet2!$S$1,0,0,COUNTA(Sheet2!$S$1:$S$12)-COUNTBLANK(Sheet2!$S$1:$S$12),1)
Go to sheet 1.
In B1, I1 and P1 enter your house 1, 2, 3 Headers as you wish them to be.
Now select B2 down to B13 and Data tab > Data Validation > Allow > List > Source window > =House_1 > OK.
Do the same for columns I and P cells 2 to 13 with I columns. I source window =House_2, P source window =House_3.
You can now select from the drop downs starting with the first drop down below the header and then the next etc., so your list of repair items will be right below the header. And you can only select a repair item once. Once you make a selection, that item is removed from the named list on sheet2 for that House. Select all 12 items and there will be nothing more to select. Notice you can select any item from top to bottom from any of the drop downs.
To reset a House column, just select all the entries under a House header and delete them. You are loaded and ready to go again.
Howard