Is my 2005 Fiesta worth repairing?

We have a 2005 Ford Fiesta which we noticed one day had no coolant. I took it to the garage and they pressure tested it and diagnosed a cracked expansion tank, which was replaced. A few days later I found a wet patch on the driveway. I checked the coolant and found it was empty again. The garage pressure tested it again and two leaks were discovered, one at the thermostat housing and another in the radiator. The garage tells me that the repair is not too bad but the mechanic suggested that there could be an underling issue causing repeat leaking in the coolant system (head gasket issue). My question is: do you think it's worth repairing given the suggestion of a possible head gasket failure - or do you think there could be an underling issue?
If they have pressure tested it then the pressure test would find the weakest points but would not necessarily find all of them and running without coolant could have caused a cylinder head or head gasket problem. Getting the radiator and thermostat housing replaced is a risk, but the car is worth buttons otherwise so it's a risk worth taking.
Answered by Honest John on

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