It's there, on the shelf. There, right in front of you, you idiot!
I find it very hard to believe that Travis's business is so unusual that an off the shelf system could not be readily tweaked into usefulness.
A quick rummage around in some old B&Q/Homebase/whatever news items would probably reveal the providers of their IT solutions, who I have no doubt would love the opportunity to double their money on a tried and tested system, that requires perhaps 6 months of bespoke jiggery pokery.
Sure enough, everyone will need retraining to fit in with the new system, but that was always going to be the case.