What would have been the most helpful thing to know when you were buying a 3d printer

[ONUS]

For those of you that own 3D printers, what would have the been most helpful bit of information to have known when you purchased your printers? If you could go back, what would you have been more careful to look into, and what specs would have been most important to you?

[bshadown]

Max temperature and type of filaments it used

[Geoff]

It's much cheaper and more fun to build your own rather than buy a pre-built one. With a pre-built you are often stuck with design flaws that show in prints and are much harder rectify, whereas a machine you built yourself you know inside and out and know why things happen (or don't). But, that being said if you can buy a pre-built very cheap, as in $500ish, buy it simply to save yourself the time and hassle and use it to make parts for your new one.