How do you protect yourself? First, since repairs should be completed by contractors like electricians, plumbers, HVAC technicians, and so on, ask for receipts. Sometimes the sellers will try to fix electrical issues themselves, but the odds are pretty good that they will do it wrong. Moreover, there is a reason electricians go to school and require a test to become an electrician. You wouldn't ask an electrician to make a gourmet meal or fly a commercial airliner. Why would you be ok with a seller making electrical repairs?
If they cannot come up with invoices, then pay me to have a repairs inspection. Cost is minimal and I have seen repairs that make me shake my head. For instance, one time the repairs to the electrical panel which disconnected power to one bedroom. That's right no power to the receptacles, light fixture, or ceiling fan. Good thing my client hired me.
Call me when you are ready for an Excellent Home Inspection.