You can launch any number of commands before an INF install section is executed. Standard LDIDs can be used in pre-install command sections, but Custom LDIDs can not.
[InstallSection]
RunPreSetupCommands=<CmdSection1>[:flag][,CmdSection2[:flag]
[CmdSection1]
myapp1.exe
myapp2.exe
[CmdSection2]
myapp1.exe
myapp2.exe
Quiet 1
NoWait 2
Default flag is not quiet and wait for command return.
The RunPreSetupCommands section is executed after the begin prompt.