Hi, I would like to stay a couple of months in Thailand soon. My goal is to relax and do some sport (bodybuilding). What would be my budget? Where can i get information on renting an appartment? What are the prices? Am i beter in a cheap hotel? I don't need luxury, as long as its clean and safe and close to or in the city i'm happy, 1 room and a bathroom is okay for me.
googling "aparments in bangkok" will help you out plenty. There are plenty of apartments in the centre of the city that you can stay at and plenty of gyms that you can join too!
I think you would be better off in Pattaya than BKK. Much smaller, cheaper, on the water and most places accessible by walking or the baht bus, 10bt per trip. The are many places to stay under 7,000 baht/month. Take a look at the Pattaya Mail newspaper online and you will see what is available for monthly rentals. Many of the hotels also offer monthly rates at affordable prices. That will probably be your best bet for a few months. Most have small fridge in the room, no cooking however. Meals are so cheap in local restaurants that it does not pay to cook anyway. Many have pools as well.
There are many choices in Pattaya for lifting weights. Tony's Gym on 3rd Road is the most popular, but there are other places as well. Chevin's Gym on Soi Day-Night is not as nice, but cheaper rates. PRS Gym on Soi 17 is the cheapest place to workout that I know of.
Send me a PM if you have any questions.