Qualcast 53 Cm Self Propelled Petrol Lawn Mower

I have to describe this as a non runner unfortunately.Not sure how to describe the problem with this mower it is a Qualcast SELF PROPELLED KEY START, Briggs and Stratton 161 cc engine. It is in the most part excellent condition as you can see in the pics, it cuts and runs beautifully, engine runs like new (no smoke) or anything like that in fact it hasn t seen much work, the problem appears to be the starter battery. I paid £500 for it new so you know its a top of the range mower, The issue is its a sod to start sometimes for some reason, sometimes it starts first turn of the key other times it will just click when you turn the key. If you come to see it you may see it running like a new mower or not running at all if its in the mood not to start. I am not mechanically minded in any way so its not my thing to tinker with it. You may sort out the starting issue in two minutes or you may have to buy a part for it I just don t know, the only thing I can assure you of is once it starts it runs like new and works faultlessly. I should mention that once (if) it starts it will start again without problem if that helps. The battery charges quickly and has test lights on it and as you can see in the picture when you press the test button it shows fully charged with 4 green lights so don t know if any of the issue lay in this area? I rang my brother-in-law who is an electrician and he suggested that perhaps the battery loses its power when its put under load to start it, He lost me at that point. Anyway getting back to the mower itself the condition is very good, cuts perfectly (blade is excellent) it also has a mulching thing where you can take the grass box off and attach it on the side (shown in picture) All I know is I can t be bothered with something temperamental. Any questions, please ask, pick up only near Dereham (mid Norfolk) Thanks for looking