If you have invoices that are the same amount for the same client and are billed weekly, bi-weekly (every other week), monthly, or yearly, you can set them up as recurring invoices. 

To set an invoice as a recurring invoice, just select the frequency of the invoice when setting it up. After sending the first invoice, the subsequent invoices will be generated automatically. 

For example, if you send an invoice to Client A for $100 and set it up as a monthly recurring invoice on January 1st, Hurdlr will automatically generate and send that invoice on February 1st, March 1st, etc.