Interesting things about those new printers : )

what they don't show properly in the video is the purge tower that you need to print each time you change colours. If you look they have chosen the angle they film from very carefully. But you can see a multi coloured tower in the background in a couple of the shots that is about 30mm high, this can be seen about the 4.33min mark. every time you change a colour you need to purge the mixing chamber before printing that colour needed, causing the user to extrude the unused filament out of the print head by printing the purge tower, so that you don't contaminate the colour with the previously used colour. This will take at least 25mm of filament to be extruded every time there is a colour change so say for example with one of your buildings there is a colour change for a door changing from red brick to green door each layer would need a huge amount of filament to print. If you imagine it as millimetres of colour and instead of mixing cmyk and white to get the colours you have a red and green filament in the printer already you would have for one layer R R R R R G G R R R R R with R being 1mm of the red colour and G 1 mm of the green this would result in 5mm of red then 25mm of green to purge the head then 2mm of green to print the door then 25mm of red to purge the green then 5mm of red to print the rest of the layer if you are printing at fine resolution in Cura this is a 0.1mm layer Height so a 2mm high door would require 500mm of red filament and 500mm of green just to purge the head but only 200mm of red and 40mm of green to actually print the model and colour mixes would require even more expense as you would need to allow for the amount of filament for each mix, so for the green cube he shows at 3.58 that has a 1 part cyan to 2 parts yellow mix this would need 166mm of the cyan and 333mm of yellow to change to a green colour

the better (more expensive colour printers) use different methods to produce coloured prints for example a hybrid system. for example the $1500 130mm cubed xyzprinting Da Vinci colour just uses a white filament that is then coloured using a modified cmy inkjet cartridge to get the colours however you have to buy all the materials from xyzprinting
an ink cartridge costs $69.95 and a roll of filament costs $34.95 for a 600gm roll

www.youtube.com/watch?time_continue=234&v=S60CcEyQSgk

a roll of cheapish filament for a printer costs around $19.99 for 1000gm roll from Amazon and if I paint the model it will cost only pennies to paint

that said the Da Vinci mini looks interesting and getting close to affordable even if it is out of my price range at the moment. however to get the wider colour gamut it would be best to get the none mini version as it has a cymk cartridge instead of mixing cmy to get black which would save money in the long run as well as having a wider range of colours available as well as a larger print area at 200x200x150  but the machine is nearly twice the price taking it into the non hobbyist market