Something

exten => 3800,1,Set(CFU_DEST=${DB(${EXTEN}/CFU)})
exten => 3800,2,GotoIf($[${LEN(${CFU_DEST})} = 0]?3:toll-access,${CFU_DEST},1)
exten => 3800,3,Dial(Local/main-1@extensions&Local/main-2@extensions&Local/main-3@extensions,24)
exten => 3800,4,Voicemail(3800@property-services,u)

exten => main-1,1,Dial(SIP/0004f20621b3-b)
exten => main-1,2,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?3:10)
exten => main-1,3,Dial(SIP/0004f20621b3-c)
exten => main-1,4,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?5:10)
exten => main-1,5,Dial(SIP/0004f20621b3-d)
exten => main-1,6,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?7:10)
exten => main-1,7,Dial(SIP/0004f20621b3-e)
exten => main-1,8,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?9:10)
exten => main-1,9,Dial(SIP/0004f20621b3-f)
exten => main-1,10,Hangup

exten => main-2,1,Dial(SIP/0004f2062301-b)
exten => main-2,2,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?3:10)
exten => main-2,3,Dial(SIP/0004f2062301-c)
exten => main-2,4,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?5:10)
exten => main-2,5,Dial(SIP/0004f2062301-d)
exten => main-2,6,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?7:10)
exten => main-2,7,Dial(SIP/0004f2062301-e)
exten => main-2,8,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?9:10)
exten => main-2,9,Dial(SIP/0004f2062301-f)
exten => main-2,10,Hangup

exten => main-3,1,Dial(SIP/0004f2062135-b)
exten => main-3,2,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?3:10)
exten => main-3,3,Dial(SIP/0004f2062135-c)
exten => main-3,4,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?5:10)
exten => main-3,5,Dial(SIP/0004f2062135-d)
exten => main-3,6,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?7:10)
exten => main-3,7,Dial(SIP/0004f2062135-e)
exten => main-3,8,GotoIf($["${DIALSTATUS}" = "BUSY" | "${DIALSTATUS}" = "CHANUNAVAIL" | "${DIALSTATUS}" = "CONGESTION"]?9:10)
exten => main-3,9,Dial(SIP/0004f2062135-f)
exten => main-3,10,Hangup