I got two car wheel nuts welded back to back, I keep it under the seat in case the rac man does not have a tool.
I change my own tyres using, my jacked up astra with spare wheel rim fitted as bead breaking tool , I put an old car mat down to protect the wheel from ground abrasions, you need to be carefull with the front just tip it upwards at the rear to avoid presure on the brake discs, or alternatively a front wheel will fit in a large vice .I have cheep balancing tool bought on e bay for not much. If you have trouble making the beads seal when inflating the fitted tyre, just blow up a car wheel to about 60 psi remove the valve on the bike wheel and fit a foot pump hose of similar betwean the car and bike tyres, Ive fitted lots using this system , but if you are not confident in these things you must pay yer money etc, I would not change tyres before they are due, as they are expensive enough to change when they are knackered.