The custom VDS builder offers flexibility; but striking the right balance is critical for performance and cost.
CPU or RAM?
Web and API servers are generally more sensitive to CPU, while databases and cache layers are more sensitive to RAM. Measure your workload; adding resources without knowing where the bottleneck is wasteful.
NVMe size
NVMe provides high IOPS; but rather than buying more disk than you need, track your growth trend and resize when necessary. A resize via the API completes in a few seconds.
Cost optimization
If you are a reseller, since the discount applies to the base price, right-sizing reflects directly in your margin. Starting small and scaling with demand is the healthiest strategy in most cases.