When you send an invoice with a file attached, your client will see a link to download the attachment in the invoice email message. If you send your client a link to view the Web Invoice in Harvest, they'll see the link there, too.
Sales Tax: Depending on your jurisdiction and type of business, the tax requirement can get complicated. Be sure to follow instructions from your local tax bureau and include the appropriate tax amount on the invoice. Pro tip: Use an invoicing software to manage your business activities, change tax settings as you want and make your tax time easier.