Multiply columns MS SQL

Question

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

 

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'