For light usually tap from socket... jimat sket.. and if for socket or high amp electrical item i usually will take from DB.....

But if your load not exceed.. should be ok to combine light and 1 aircond

Depends bro... usually they quot me between 40 to 140.. conceal or not? Distance... have to ask wireman to come and gip quot.. as some just lay wire using old route...connect toplaster ceiling