1. Buying the Least Expensive System
We all want to save money when buying stuff, but with computers this can lead to problems. Often times the spectacular deals offered on systems have hidden caveats that users are unaware of. The most common issue is older outdated systems sold for minor savings instead of spending a bit more to get a dramatically better PC. Always price compare and look at the individual components to be sure that it really is a good deal and not older technology at slightly discounted prices.
2. Not Budgeting For Peripherals and Software
While most computer systems tend to come with a little software and may be bundled with items, the prices do not cover all the items you may need to use your computer effectively. Often times there are peripherals such as a printer, power strip or cables that you might need to protect and use your computer. The software is a bit trickier though. PC manufacturers typically include limited software that might meet some needs but not all. For example, anti-virus packages tend to include 30-days of updates, but after that its necessary to purchase the subscription updates.
3. Subsidized Computers
A new trend especially for netbooks or laptops enabled with WiMAX and cellular modems is the subsidized PC. These are laptops that have rebates attached to them discounting the systems from their normal price. The downside is that the buyer must purchase a long term service contact with the cell provider or ISP. In order for these to work, the ISP rebate has to be less expensive than the discount on the PC. Be sure to see what the financial commitment is before buying any subsidized PC to ensure that you can meet the terms and it is something you really want.
4. Extended Warranties
Retailers really are pushing these and for good reason. The margins are quite low on consumer electronics and computers but extended warranties are worth a lot. When consumers buy one, they are essentially betting that there computer will fail before the given date. Consumers tend to end up on the short side though as most failures will happen long after the warranty periods and by the time they do, the items in question are outdated. The money can be better saved for future replacement costs. Even organizations such as Consumer Reports recommend against purchasing such warranties.
5. Waiting For Something Better Later
Newer and better technologies are always coming. The problem is that knowing when such technologies are going to come out is not an easy thing to do. No matter what technology you buy into with a computer, it will be outdated in the future. The problem with waiting for that next technology to come out is that you generally end up spending more for the newest thing or you are left without something that you could be using now on the promise of something better later on.
6. Unbalanced System Components
Have the latest and greatest processor but not enough memory to run your applications? What about having enough RAM to run you programs smoothly but not enough drive space to store your programs and data? This is something that consumers have a hard time judging as they might not know their needs until they start using the computer. The problem is that with some computers these items may be hard or impossible to upgrade. Always try to research and be sure you are buying what you need now or that it has the ability to be upgraded in the future.

