Assistance required with which formula to use to create a Master sheet referencing other workbooks

[Buttontoes]

Hello everybody I am seeking so advice on how do collate a summary for the financial year of the invoice date, hours worked, the associated codes (possibly 4 per invoice), and total dollar value.


Thanks in advance


I generate weekly invoices with the (day In Column A), (the date in column B) (hours worked In Column C), (Services Description in column D, "from a drop-down list"), (the hourly rate in column E, "=VLOOKUP(D17,VRate,2,0)"), and (total in column F)

Refer details below:

DAY	DATE	HOURS	DESCRIPTION	HOURLY RATE	TOTAL
Sunday	27-Jan-19	2	Care Assistance (Sunday) 01_014_0107_1_1	$85.14	$170.28
			Community Participation 04_104_0125_6_1	$48.14	$0.00
			Personal Training 12_029_0126_3_3	$55.72	$0.00
Monday	28-Jan-19	3	Public Holiday 01_005_0104_1_1	$107.00	$321.00
			Community Participation 04_104_0125_6_1	$48.14	$0.00
			Personal Training 12_029_0126_3_3	$55.72	$0.00
Tuesday	29-Jan-19	2	Care Assistance (Evening) 01_015_0107_1_1	$52.17	$104.34

<colgroup><col><col><col><col><col><col></colgroup><tbody>
</tbody>

All of these invoices are stored in the SAME DIRECTORY with CONSECUTIVE NUMBERS for example
Casey_Brown_Invoice_201
Casey_Brown_Invoice_202
Casey_Brown_Invoice_203



What I am trying to do is get a Master Sheet Summary of all the invoices in the directory.


Currently, I can achieve this in the worksheet by using


"=SUMIFS(C17:C37,D17:D37,"=Care Assistance (Weekday) 01_011_0107_1_1")"



The invoice "Date" in cell F3 every time
The total number of "Hours", >0 spent on each Service Description
The "Service Description" cell could be variable
The "Total Dollar Value" cell could be variable


I hope this is not too complicated I am just trying to provide as much information as possible. Thanks again in advance.
Peter