Could use some advice

[Mathew Saunders]

You don't need to add a heated bed. It already has a heated bed. Did you read the technical specifications? It says it has a heated bed in two places:
You should be good to go! And that does look like a nice printer!!! With free shipping!

Prusa i3 Technical Details

• 8″x8″x7.25″ (20cm x 20cm x 18cm) Build Envelope
• RAMPS 1.4 Electronics
• 6mm Acrylic Sheets as Side Support
• 0.4mm J-head MK IV Hotend
• 50 micron Layer Height Aachievable
• MK2A Heated Build Platform
• GT2 Pulley’s and Belts
• 12V 15A Power Supply
• Greg Frost’s Greg’s Extruder

Included in the Prusa i3 Package

Prusa i3 Electronics

• MK2A Heated Built Platform (wires and LED pre-soldered)

Thanks for clearing that up, I couldn't find the tech specs? Anyways, it looks appealing. It seems to be a really fair price!