I have a tiny garden and i try to re-use last year's christmas tree. Bought one 60cm high, this year it's 80cm (and significantly harder to dig out of the ground, it has a healthy root system). We'll see how many years it'll survive, and how many years it is physically possible to put it in a big bucket and move it indoors.
Real trees simply look better. But plastic trees are of course a lot cheaper if you want a big one every year. Compared to other 10-15 year old trees, christmas trees are surprisingly cheap, but a human-size one can easily cost 50 euro.
(Side note: incandescent multi color mini lights in the tree, color 27 'Incandescent Fluorescent' lighting the dark corner at night - and a 2,4m long t12 tube in the corner that lives there because it's the safest place for it)