If you are using Smartspec on a Free Plan you will only be able to export a partial project specification (this is an example project only and contains a limited number of specifications and sections)
Purchasing a project from the project export page
When you go to Export your project you select Save to PDF to access the partial project specification or you can click Purchase this project to unlock
Selecting Purchase this project to unlock will take you to the payment page where you can enter your credit card details.
Selecting Save to PDF will take you to the Export project page where you will be given the option to export the partial project specification or to use one of your purchased project allotment to export a full project specification (if you have no projects available you will be taken to the payment page).