Moving the stop tap and waste in the kitchen

Without looking at the job I would imagine its not an issue to move the stop tap 1m to the right, providing there’s no issue with having a small bit of pipe work run along the wall at low level, the easiest solution would be to just run it along the wall beneath or behind the new cabinets your installing.

I think this would be very difficult, you should look at remodelling your design so that this does not become an issue. If you are adamant that you want them moved you will need to dig up the floor and isolate the mains water supply out in the street, be very careful not to hit the pipes as you progress, once you have exposed the pipes below ground level you can get a push fit coupler (elbow) 15mm from screwfix for the water main pipe and a 40mm universal compression coupler (elbow) for the waste pipe and extend them in to the new sink space either below ground level or against the backwall, protect the pipes once complete and apply a week concrete mix over to enable the dishwasher to sit in place good luck.

like michael said it will be outta sight and outta mind and cost you no more than £80-£120. But i know customers who would rather pay £300.00-£400.00 to have come thought the floor🤯

I personally would prefer not put a push for below ground. I would try to fit pipe behind dishwasher. As previous reply said, be very careful not to pierce pipe if you do decide to dig up the concrete