I have a current model Macbook Air 13" w/ 4 Gb of ram. I do a whole variety of development (PHP, golang, python) with MongoDB and MySQL. Currently, I have a f

I have a current model Macbook Air 13" w/ 4 Gb of ram. I do a whole variety of development (PHP, golang, python) with MongoDB and MySQL. Currently, I have a few tabs in the terminal open connected to a few servers, MongoHub (MongoDB client), Sequal Pro (MySQL client), Firefox (2 open tabs), Chrome (15 open tabs), Sublime Text 2, Spotify, Cyberduck (FTP/SSH client), MAMP Pro, iTunes (phone is backing up), Adobe Reader, VLC and Excel open. I usually have those, along with Photoshop and Parallels opened as well and haven't felt any slowdown at all. I'm using the Microsoft Wireless Keyboard 800 and Microsoft Bluetooth Notebook Mouse 5000, have a 23" AOC monitor hooked up via Displayport to HDMI adapter from Monoprice. This setup was probably around ~$1500 without any warranties. I just picked up a nice SD card that is sized to fit almost flush with the Macbook Air and is 128 GB w/ a fast 90 MB/s read/write which I can use as a file dump, that cost around $50 on Amazon, but worth picking up a few if you want to isolate projects or just use as backup. Unfortunately, the Macbook family isn't too upgrade friendly so you may buy a laptop and it may be underpowered and until you refresh your hardware, you'll be stuck with that hardware, so it may take you a few years to get the exact setup you need. This is why people recommend maxing out as much as you can with RAM and expand hard drive modularly. I'd honestly recommend not going with an older model laptop or desktop because HD space is going to end up being your bottle neck, not RAM, and the newer lineups have USB 3.0 so you want to be sure you get that, then you can pick up a 1 TB external USB 3.0 HD for $100 and won't suffer with USB 2.0 speeds.