Indeed, there are a lot of engineering challenges related to the distance. Solar power is much, much dimmer at 900 AU -- that's like 20x Pluto distance -- so you'll need to bring something like an RTG. But your RTG will decay while the spacecraft travels (Voyager's RTG has already lost 30% of capacity). Once there you'll need a lot of power to transmit data the back with any sort of speed or reliability. All of this is on top of the usual telescope-reliability concerns; in many ways it would make the James Webb telescope mission look straightforward.

This is one of the reasons for papers such as this one: exploring what meaningful solutions to these problems, and meaningful mission profiles, would actually look like in practice.