How can I improve the performance of this select into query - sql-server

Question

I would appreciate if someone advises on how to improve the performance of a stored procedure with the following query (the functions are very small and I don’t believe they are penalising the performance):
SELECT DISTINCT REPLACE(REPLACE(REPLACE(c.[description], ' Org',''), ' group',''),'Organization full name','Org')
AS OrgColumn1,
REPLACE(REPLACE(c.[description], ' Org',''), ' group','') + ' Organization' AS OrgColumn2,
CASE
WHEN dbo.fn_OrgGrantPageAccess(c.id,#contactId) = 1
AND (c.id <> 13 AND c.id <> 31)
THEN '<a href="OrgMainPage.aspx?id='+CAST((c.id) as varchar(15))+'">'+
replace(replace(c.[description], ' Org',''), ' group','') + ' Org</a>'
WHEN dbo.fn_OrgGrantPageAccess(c.id,#contactId) = 1
AND (c.id = 13 OR c.id = 31)
THEN '<a href="OrgMainPage.aspx?id='+CAST((c.id) as varchar(15))+'">'+
c.[description]+'</a>'
ELSE
replace(replace(c.[description], ' Org',''), ' group','') + ' Org'
END AS OrgColumn3,
c.id AS OrgColumn4,
dbo.fn_OrgGetColumn5(c.id) AS OrgColumn5,
dbo.fn_OrgGetColumn6(c.id) AS OrgColumn6,
dbo.fn_OrgGetColumn7(c.id) AS OrgColumn7,
dbo.fn_OrgGetColumn8(c.id) AS OrgColumn8,
dbo.fn_OrgGetColumn9(c.id) AS OrgColumn9,
dbo.fn_OrgGetColumn10(c.id) AS OrgColumn10
INTO #T
FROM table_c c
INNER JOIN table_s s
ON c.id =s.id
INNER JOIN table_t t
ON s.type_id = t.type_id
LEFT OUTER JOIN table_m m
ON c.id = m.OrgID
LEFT OUTER JOIN table_cal cal
ON m.meetingid = cal.calid
WHERE t.type_id = 3
AND active = 1
AND (c.org_1 = 1
OR c.org_1 = 3)
ORDER BY OrgColumn1

Answer 1

I suggest you to rewrite dbo.fn_OrgGetColumn function from scalar-valued to table-valued and then cross apply it to main result set.
If you can provide source code for dbo.fn_OrgGetColumn function I can help you with rewriting it to table-valued.
There you can find good explanation with examples: Boost Your T-SQL with the APPLY