Had electrician install an outlet and light with switch.  Trench was dug by me on the hottest, most humid day of July.

This was a blue plastic drum that I got for free and painted beige.  Cut a hole for overflow and a hole for a spigot.  Only downside is that flow is somewhat slow.  I may try to raise the barrel on blocks to get faster flow.

Installed a metal gutter with downspout on the north side of the greenhouse. The gutter requires periodic cleaning from leaves.  Downspout flows into a rain barrel.

Insulation.  Used foam with reflective backing to insulate the areas with clapboard siding only.