Well not a great deal to be honest. I never understood why people use fake ones to be honest.
Some people like myself choose to add a 'compost' type material in under your gravel or sand, like i do. but it's not essential.
In terms of maintenance I would say just trimming or cutting back now and then, removing any dead leaves, dead plants etc. It's really not much effort to be honest.
If you play your cards right, you could buy a batch of bunched plants and they would end up growing big enough for you to trim, then you can use the trimmings to start again with a new bunch so you'd never have to buy any more again!
Depends what type of plants you want though!