What are Vive's entry and exit costs?

Vive itself charges no entry or exit costs. What does exist are costs the fund incurs when buying or selling underlying holdings; these are built into the fund price.

That mechanism is called swing pricing: on large inflows or outflows the entering or exiting investor bears those costs, so remaining investors are not affected. With regular contributions this averages out over time. See the swing factors per fund or the pricing.