Reversing a trailer is simple if you can see it, if you can't see your trailer then your in trouble.
Get to a big carpark and practice reversing into bays 
True, but when you get work in those narrow cul-de-sac's with cars parked in the way so you can't turn,.. and the trailer full of water means its too heavy to unhitch and turn by hand,....
I use a trailer, and wont go back, saves a lot of money on extra costs. I have 400lts, no issues, driving it is fine, very stable, and no snaking. I even forget it is their sometimes.
You soon get the hang of reversing, just practice. any half decent driver that reads up on the basics arts of driving one will find it a doddle after a while.
As for those harder locations where you made need to unhitch the trailer to turn (never had to do this yet though, always managed to get away with it). Simple solution - just leave the harder locations tilll the end of the dsay when you have a lighter load. simple !!
and yes, make sure you have a jockey wheel that will help moving it about, hitching and unhitching. A hitch lock and and wheel clamp are a good buy for security. I keep mine in the garage, which makes filling the tank easy, stright inside the garage. And no real freezing issues as it is in the the garage and with closed trailer seemd to keep it in trim over night.
I got mine from Cyrstal pure systems - trailer is a decent trade trailer, so thats probably why it is stable. - dont bother with a cheep trailer that not for everyday use.
hope this helps