Hi Wess,
If this commission is still open, I propose USD 120 for the explorable volcanic-island prototype you described, including the source project, a fullscreen walkthrough video and one scoped revision.
The layout would use a readable beach-to-cliff path leading toward the volcano, with the small building as a landmark and an alternate route around the island. Terrain materials and smoke/lava effects would establish the volcanic setting; licensed reusable assets would keep this within prototype scope. No quests, HUD or save system.
Before confirming a start date, could you confirm your preferred Unity version, target platform, approximate island size and whether the budget is still available? I suggest agreeing on a simple layout first, then checking the full walking route, collisions and volcano effects in the delivered build. A provisional delivery target is seven business days after scope and technical setup are confirmed.
This is a proposal for your brief, not a claim of prior client work. You can reply here or reach me at ycwdjb599@gmail.com.
evanworks