Conditional Formula: If Text, rep as number to sum, else sum numbers.

I can get only so far, then stumped:

• 3 columns (Hours, Rate, Amount)
• "Hours" is a 'List' with data from from another sheet.
• Data is named 'Worked'.
• 'Worked' is all 2 decimal numeric (represents total time worked), except first item called "Live In"

IF 'Hours' is "Live In", I can use:

=IF(A1="Live In", SUM(B1*1))

How can I make it conditional so that if it's not "Live In", then it will SUM(A1*B1)?

SideNote: 'Worked' LIST has total time with minutes expressed as 1/4 of hour (i.e., 1.25 = 1 hour, 15 minutes).

Thanks.