Total cost is roughly $110 USD, but there are a couple caveats to that price:

  - some parts are sold in multiples, so you'll have to buy several even if you only need one for the build
  - I ordered the electronics from JLCPCB where the minimum order quantity is 5 (minimum assembled is 2). At a quantity of 5 assembled, the LED board is ~$12/board and the mainboard is ~$41/board. If you're comfortable with SMD soldering, you can order bare PCBs and parts and do it for much cheaper by assembling only one of each board. You can find some more details here: https://oasis-terrarium.com/docs/electronics/#how-to-get-them. And a history of my JLCPCB orders including costs here: https://oasis-terrarium.com/docs/electronics/#pcb-order-history

With those caveats in mind, the rough breakdown is:

  - custom electronics: $53
  - 3D-printed parts (~600g of PETG): $12
  - other parts: $46

As for build time:

  - acquiring/assembling electronics: this can vary a lot depending on whether you buy assembled or do it yourself
  - 3D-printing: depending on your printer, maybe 2 solid days of printing
  - waterproofing 3D-printed parts: takes ~15 minutes to do and 24hrs for the epoxy to cure
  - final assembly: 30-60 minutes