The Diamond Sukumvit Condominium is on Sukhumvit Road and has its own swimming pool, fitness centre, libary, garden, parking, coffee shop and 24 hour security. It is approximately 250 metres from On Nut BTS, Tesco Lotus, Big C and local shops. Easy walking distance to everything you will probably need, and a short drive to the expressway network.
A shopping and cinema complex is being built next to the BTS station at On Nut (opposite Tesco Lotus).
The 15,000 Baht per month rent is negotiable - if you do not ask you do not get :)