How hard would it be to install a after market cruise control on a 2007 350z? Would one be better off taking it to a shop? Anyone out there ever installed one? l see them for sale around $ 300

Very confusing to install. Instructions will not help.
You should take it to the dealer to get it installed properly and quickly.

Do not do it. A CC interfaces with many sub-systems of the vehicle and this is a complicated vehicle. Anyone saying otherwise is lying to you. l am surprised that a 350Z could be bought without CC. The only choice you have is to install a factory unit but it is going to be expensive. You should have been bought it with the car the first time.

That depends.

If it is anything like a newer body style F150, you get the cruise function turned on in the computer and install the cruise control buttons on the steering wheel or that multi function switch on the column.

More pricey than difficult if that is the case.

Because most cruise controls r cable operated & ur car does not use a cable operated throttle chamber. Most have some kind of crud hooked to the Accelerator pedal. Do not do it! Not only is it dangerous to have aftermarket throttle controls it may also set a check engine light. And some aftermarket systems do not see clutch inputs so when u push in the clutch what happens? The best system came installed on the car from the factory & works flawlessly. Just be safe l do not recommend any of the systems l have seen installed so far. Unless there is complete interface of TPS & ACC signals (x2) that system does not exist yet.