Compare the base before its size
Begin with the framework your team can maintain. The catalogue includes Qbox, ESX Legacy and several QBCore starting packages, including the NoPixel-style V7 base. The latter describes a style of setup; it does not establish an affiliation with another server.
Read the included systems and version details. A large script or vehicle count is only useful if those components serve the city you are planning. Identify which jobs, interface elements, interiors and economy settings you intend to retain.
Make a setup inventory
Confirm the package's installation instructions, database needs, external dependencies and licence conditions. Record any accounts, keys or server settings you must supply. Check which files can be edited and what support or update provisions the individual listing describes.
Build the first instance privately. Create a new character, complete an ordinary job, buy and store a vehicle, then test the relevant staff tools. Reconnect and restart to check that progress persists as intended.
Only then set your branding, access rules and economy values for players. A prepared base reduces the work of collecting components, but the package still needs configuration and acceptance checks for your own server.