Yes, this is 100% possible with our app. We have a lot of bike shops as customers who use it for that use case as well.
In your case, all of this can be done right within POS. For example when a customer comes in and requests a repair, you can go ahead and create "New Draft Order", select your customer, the workflow status (e.g. Open, Pending, etc), add whatever line items you want (e.g. 1 Hour Diagnostic for 60 minutes at $75 per hour), add any notes you want to specific line items or the draft order overall, create the draft order, and whenever you're ready add to cart.
Note, you don't need to add to cart right away... You can create the draft order, let it sit there, and you can always revisit that same draft order and make edits to it (e.g. adding new charges/repairs/line items), and then when you're ready to check out the customer, add it to the POS cart and checkout the customer in person.
All of this can be done within POS, no need for your staff member to go into Admin anymore. I've attached a sample image below.