think the majority of them don't need much fiddling to be fair, think it only gets slightly fiddly when you want to hardwire it into the power rather than using the 12v/cig out for the power source
some I think can be battery (their own internal) powered so can avoid the need of any cables in the car, just stick it to something...but then you'll need to remember to take it out in the evenings to charge probably
plenty of cheap and cheerful ones on ebay that have had good reviews from several members on here. can also get a variety of apps that turn your smart phone into a dash cam, downloaded one myself but have yet to actually test it (need to replace my phone holder as mine broke

)
suppose another key point is how much are you willing/aiming to spend as they can range from about £20 <720p30fps simple jobby, up to £400ish for dual cams with GPS in 1080p60fps singing and dancing etc etc