They talk the talk, but failed to walk the talk.... failure to standby their FIXED price promise. Went through the quote process, stating a conversion from system to combi storage, to which a premium is already added. The fixed quote was £3,750.00. I uploaded 9 images (twice as they said they couldn't find them). The photos were clear in showing the existing installation and even included schematic diagrams with heating calcs also included. Heatable engineer (sub-contractor) arrived as expected, inspected the job, stating an additional wired thermostat and 3 way value would be required, required and promptly phoned Heatable, they contacted me stating they required a whooping £750.00 - 20% more!!!!! I point blank refused to such a steep hike. One would have thought that the free gas pipe installation and the magnetic filters services offered as free but not required would of offset the additional 2 items required. I have already had quotes for the same, another installation service was now priced better (includes 5 year servicing plan - 10 year parts/labour warranty) or like for like by over £500 less than Heatable, and they have actually seen the job on a survey... Charlatans.