Each year N-Registered aircraft will require an annual inspection by an IA (FAA Licenced Inspector Authorisation). This annual inspection will be preceded by the maintenance tasks required to ready the aircraft for another year’s service. Much of the work falls under the banner of "preventive maintenance" which means "simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations". These tasks can be carried out by a Private Pilot and here is a good article explaining things in a little more detail here
The annual inspection should cost approximately €600 or £510 provided the aircraft is presented properly, which ideally is the maintenance tasks completed, log books up to date, aircraft clean and indoors. You may need the A&P IA for other task during the year such as for inspecting STC modifications or signing off revised weight and balance data etc. We have available the services of a friendly A&P/IA and are happy to recommend him. Contact us for details.