Multiplication of two columns MS SQL

Query is ok
 
In table mp_racun_roba (down in query) i have column name kolicina
 
1) I need to multiply this three column with kolicina
2) In sum column if have value with thousand separator not sum (example 1,644.00) just jump that value

UKUPNObpdv  UKUPNOpdv  UKUPNOsapdv
   132.00     22.44      255.06

SELECT SUM(isnull(cast(REPLACE(TRY_CONVERT(float,TRY_CONVERT(float,iznos_bpdv),1), '#,0.00','')AS decimal(10,2)),0.00)) as UKUPNObpdv,  
SUM(isnull(cast(REPLACE(TRY_CONVERT(float,TRY_CONVERT(float,pdv),1), '#,0.00','')AS decimal(10,2)),0.00)) as UKUPNOpdv,  
SUM(isnull(cast(REPLACE(TRY_CONVERT(float,TRY_CONVERT(float,iznos_sa_pdv),1), '#,0.00','')AS decimal(10,2)),0.00)) as UKUPNOsapdv  
from mp_racun_roba  
where tip_robe='Roba (Generalno)' and id_fakture='34'