Picking up a girl is easy in Pattaya. You don't have to find them, they find YOU.
Taking a girl to your hotel might result in an extra cost at the reception. But there are enough good hotels in Pattaya however where you don't have to pay, here are some girlfriendly hotels where I stayed myself:
Welcome plaza South Pattaya
Dynasty Inn
Sunshine (ask for new wing, in the middle of the action on soi 7)
Flipper House (on of my favourites, in the middle of the action on soi 8, but you'll need to make a reservation)
Queen Pattaya Very good location on central road near supermarket Tops
any sawasdee hotel
Lek Hotel Best breakfast in town! Also reservation necessary, always full.
Welkom InnNext to Sabai hotel (also good and girlfriendly) in North Pattaya, near the soapy Sabai room...:-)
Laatisowaat!!!
