Dear Exc4
It is a bit long but I think the following array formula (in A16 and copied down) does what you want without any helper columns
=SUM(Table1[Value ($)]*Table1[1]*(1=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[2]*(2=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[3]*(3=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[4]*(4=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[5]*(5=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[6]*(6=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[7]*(7=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[8]*(8=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[9]*(9=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[10]*(10=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[11]*(11=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[12]*(12=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[13]*(13=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[14]*(14=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[15]*(15=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[16]*(16=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[17]*(17=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))+SUM(Table1[Value ($)]*Table1[18]*(18=Table1[Payments]+ROUND(DAYS360((DATE(YEAR(Table1[Date]),MONTH(Table1[Date])+Table1[Payments]+1,0)),A16)/30,0)))