Hi , I don't know the area so difficult to judge prices but looking at the others on Rightmove search for Flixton the pricing is ok
I would be suspicious that the work carried out opening up the ground floor was not compliant to current building regs, the pillar would normally be a steel and be triple boarded in a kitchen , of course this may be just the photo and you find that it's not brick but wallpaper to look like brick
I've had two houses opened up with the stairs open to the kitchen - not in the kitchen like this but larger open plan area with kitchen in part of it and stairs in another part but no doors in between as a fire break these were acceptable to building control providing the smoke detectors were independently wired
The alley way outside looks very narrow , is the side of your house and is access to the garages behind so the neighbours can drive through 24/7 ? This would be a deal breaker for me , you also have a door that opens up onto it .
I think if you are not able to proceed before the Stamp holiday runs out at the end of March there will be more houses to choose from in the new year and something more suiting your needs will turn up
Being both excited and scared is good ! You can definitely do this.
Excited gets your blood pumping , gets you out there looking , scared makes you check that everything is correct and as it should be and stops you running away with the wrong house 😀