hi, i drive an Honda jazz 2003 1.4 and it was running perfectly, the other day i ran the battery down (completely) then took the battery to the garage and got it charged properly and I'm 100% sure theres over 12.45 V currently in there, but for some reason the car won't turn over when i put the key in the ignition, it turns fine and the hazard lights and the horn works fine and the fuses look good also, however nothing else does, please can you help me before i have to pay loads of money which i don't have
Most likely the main power fuse is blown. Was the battery load tested. In most cases when a battery is run completely flat, they are damaged. If you tried to jump start it, you probably blew the main fuse. Lights and radio require low amperage as the starter may require a great deal and not function. The battery may read over 12 volts setting still but under load may drop well below the usable threshold.
I use a Battery load tester like this one.