Is renewed track rod a sign of accident? Air conditioning loses fluid

Moin, I’m about to buy a V50 1.8 petrol BJ 2008. Now I discover that on the last invoice of the seller is “purp bar renewed”. Is this an indication that there was a damage or does it have to be done anyway with the 50,000 Insprection? Besides, the air conditioning unit loses liquid, but the workshop has found no fault and only filled up. What do you think? Is a certain loss normal? Or would you suggest that there is something on the capacitor (it seems to happen more often)? The latter would be a rather expensive repair. And – are the new capacitors more stable? Or does someone have an idea how to prevent it? I spontaneously get the idea to put a wire grid in front of it. But I have no idea whether this would be technically feasible. Thank you for your assessment, Schorse P.S.: The Volvoman around the corner meant a capacitor exchange with about 600 Eur to make a book. Since the Ford Focus 2 should be construction-like: Would the capacitor there be somewhat cheaper?