Can I send one Invoice to a Partner whith severall Invoices at the end of the month?How can I manage this?

Greetings, @webmaster-bikesa. We understand that sending one invoice with multiple entries inside is very handy on your end. You're in the right place since we encounter similar concerns here. And I'll be willing to teach how we do it.

There are two ways to send multiple invoices into one file to your partner. The first is by sending customer statements, and the second one is by creating an invoice with multiple category entries.

Sending a customer statement will let your customer view their outstanding invoices and invoices that will soon be overdue. This will place all invoices for one month and send them to your customer. Here's how::

1. Go to Sales.
2. Select Customers. 
3. Find and click the customer you want to send the invoice.  On the upper right corner click the New transaction tab.
4. Choose Statement.
5. To view the details of the statement to ensure accuracy, tap the Print or Preview section below.
6. After verifying, tick the X icon to go back. Then, click Save and send.

You can read this article for more details: Create and send customer statements in QuickBooks Online.

Another way around this is to create an invoice with multiple category entries. Feel free to follow the steps below:

1. Click the +New icon. Select Invoice.
2. Choose the Customer you want to send the invoice.
3. In the SERVICE DATE column, enter the dates of the invoices. Then, in the PRODUCT/SERVICE column, pick the Bike Rental.
4. Review the RATE and AMOUNT if correct. After that, click the dropdown arrow inside the green colored button on the lower right corner and select Save and send.

We'll also add these articles to help you manage your invoices:

• Add an account summary to an invoice in QuickBooks Online.
• Send invoice reminders automatically or manually in QuickBooks Online.
• Customise invoices, estimates, and sales receipts in QuickBooks Online.

If you have additional questions about managing your invoices, don't hesitate to reply to this post. I'll be willing to lend a hand. Take care, and have a good one.