I bought a proform 585tl about 5 years ago, its an old model now. Generally use it three times a week when I'm in a decent routine. It was 900 punts at the time. One of the bearings is just on the way out but I was able to order a replacement roller for about 40 euros.
When deciding to buy an expensive peice of training equipment you need to figure if you are the type of person to keep a routine going. I work from hoome so I can take an hour most times of day to go for a quick run as it suits. Fitting in a gym visit can be difficult with a busy schedule and other home demands. I'd suggest seeing if you can get into a routine of general exercise before you buy and see if it suits you, say book a one hour slot 3 times a week in your diary to do some press-ups, squats, short run or whatever you like and see if you can stick to it.
For me the 900 punts was well spent considering the extra time saved in travel and annual gym memberships fees required over the same amount period of five years.
Also, most gyms will offer a free (multi)session pass which you use to test their services out.
If you decide to buy a running machine, take your runners along to the shop and test drive the ones you are thinking of buying. If you have neihbours or might put it up stairs, think about the noise each one makes, some are noiser than others. DC motors tend to be a bit quieter for some reason. Avoid any gimmicky add ons. Check the size of he machine for fit in your space, most fold but can still be quite bulky.
To keep youself motivated you can get a heart rate monitor (like those at ) to track your fitness level either in spreadsheet or some specialised fitness tracking software. I use mysporttraining for windows at
http://www.vidaone.com/products.htm. This helps you see your gains over time which can be harder to see in other ways.
hth