$600. Great specs, everything you'll need. i5 processor (they make i3, i5, i7). SSD hard drive will make it quick. 8gb memory is sufficient for your needs. 16gb is preferable, but again overkill for your needs.
Most laptops will only have a single HDMI. My opinion, buy the laptop and a couple wireless keyboard/mouse combo's. Just plug in your monitor to the HDMI port and the USB sensor for the the keyboard and you're good to go.