If the noise is sharp and metallic it could be a lifter but if it isn't constant it probably isn't a problem.
Oil viscosity is a major cause of lifter noise in the models that I play with.
A/C off, Heat off and fan in the off position would eliminate A/C clutch engagement at odd times and heater valve cycling.
If it a high light tick it could be a fuel injector opening and closing.
If you want it and it is what you want get it if you can afford it.
You don't seem like the type that would live on the rev limiter so it should have lots of good miles left with good care.