It really depends on what you will be doing with the laptop.
My mom purchased one with 9 hour battery life, I think 6 GB of RAM (she doesn't know or care), a 15' screen, built-in Wi-Fi for around $300. All she uses it for is running MS Office and demoing videos when she's at bookstores, so it's perfect for her modest needs.
I also like what Andar wrote above. You need to consider what you might want to do, and make sure the laptop also fits in with that. You can NEVER upgrade the video card or processor in a laptop. You can upgrade the hard drive and memory, the latter up to the maximum the motherboard allows.
Personally, the bare minimum requirements I would have for a laptop are:
- 6 GB of RAM (this can be upgraded at least to 8 GB of RAM if necessary)
- 500 GB HD space
- Intel Core i3 or better
I assume, obviously, you'd be using RPG Maker VX Ace or XP, but I don't think either of these programs has heavy resource requirements. Any modestly priced laptop you purchase will more than fill the bill.
So, if all you are doing is: RPG Maker, browse the web/e-mail, play Facebook games, play older or non-3D video games, use a word processor/spreadsheet/etc, just about any laptop will do. I would make sure the laptop has a built-in CD/DVD drive, but that's the only thing I'd check for. In my case, I have a laptop with, by today's standards, modest specs, but it works very well for that I do with it (basically this tier).
If you tend to have a lot of windows open, and do a lot of stuff at once, you might benefit from more RAM or a faster processor, but it's not critical.
Now, if you are doing things like: Composing music or video editing --- basically creating complex custom content --- you would benefit from a harder hard drive and a faster CPU. Here, I'd go with the Intel i7 (avoid AMD because, when running a non-multithreaded application, the Intel seems to perform better than the AMD), at least 8 GB of RAM and a 1 TB hard drive. But at this price point, you're looking at spending around, at least, $700.
For my personal uses, which fit in with the above, I would buy:
- At least 8 GB of RAM
- 500 GB HD (I would use an external USB drive for other storage and backup)
- Intel Core i7, at least 2.4 GHz
I wouldn't pay extra for a separate video chip, which would bump the cost up to around $1500 or so, because at least Dell only puts that option in their higher end laptops with more RAM, a bigger hard drive and a bigger screen. A separate built-in video chip is only really needed if you want to do 3D video games with good settings and framerates. If you're using a good CPU like the above, the onboard video will let you run 3D video games, just not as well.
Of course, if you really want to play the high end modern games on your laptop, it's time to get into the really ultra-expensive world of gaming laptops. These will have such bells and whistles as: separate built-in video chip (possibly more than 1!), huge hard drives, possibly even SSD hard drives (these are much more expensive but really boost the performance and battery life of even a modest laptop), and a lot of RAM. These start out around $1000 and go WAY up from there.
Also, the higher end the laptop, the worse the battery life, as a rule of thumb. So if you don't need an ultra-fancy machine, getting a more modest one may give you longer battery life. Personally, I'd swap out the hard drive for an SSD (500 GB costs $250 or so) because it does improve battery life and system performance (boot times plummeted from 1 minute to around 10 seconds for my desktop), but you probably can't buy that as a factory option on most systems.
I would not go with a screen smaller than 15' on any laptop. As for brands, I've had good luck with Dell (although I REALLY hate that stupid rubber nub mouse controller in the middle of the keyboard since it always interferes with my typing), Sony. My mom purchased an HP laptop. I also had a Toshiba laptop that lasted for 8 years or so --- until the battery set on fire (!), since it was an old battery.
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