Hello Blogan72
You have the option of turning on progress invoicing in the product with this feature you can create multiple invoices from one estimate and allocate either a percentage or a custom amount for each line or you can create invoice which will pull all the information in and you will see the symbol below on each ,if you click on the line you do not want to include and that symbol you will have the option to remove line.

This will mean in the estimate you will have that line to use and create a future invoice from and both i novices will have linked transactions to that original estimate.
Any questions on this let us know by replying back here
Emma