Seán here from Shopify.
I've checked this out for you here and the best bet for your customers here would be to use multiple and partial payments.
With this, you can have them pay either using multiple payment methods (such as cash for one, and credit card for another) or using partial payments to pay for some of the order now and then again later on for the rest as suits.
Hope this helps! Feel free to get in touch with the Guru team if you have any questions :)
All the best,
Shopify Support Guru