annie, elenma, cissyma,
Indeed, there is one more option for BBQ - Sai Kung "Ting Uk".
Pros: free venue, private toilets (two no.), free mahjong, free bed (only one), may be have a/c, fridge and stove are available, may have some covers during bbq, there is a beach (~5 min. walk)
Cons: May have to take taxi from, say Tseung Kwan O station / Sai Kung harbous , food and drinks have to be self-prepared