Cbrooks:
OK, you have a “grip” on your possible employment options. So, words of caution, a business visa and a work permit are required to perform any work in Thailand (even volunteer work requires a work permit). Don’t get caught without the correct up-to-date visa and the required work permit. Read through this forum and/or google Thailand work permits for additional information.
Immigration laws are enforced. Random checkpoints and sweeps of bars, hostels, guest houses, hotels, etc. do occur. Randomly and sometimes frequently, including the occasional crackdown targeting foreigner “overstays”.
Good luck in your search for legal employment. It will not be an easy task. I honestly do not recall seeing a foreigner working in any of the many Thailand hotels I’ve visited, the Executive Manager and high level chefs being the exception.
As far as recommendations on where to live. Bangkok proper is 1,600 square kilometers (600 square miles). This is a vast amount of area. Everything from squalid inner city slums to luxurious (and expensive) private gated communities. Anything you want can be found and only you and your girlfriend can decide if its up to your standards.
In your case, select your living quarters based on commuting time. Once you know where the two of you will be working, and entertaining, shop around. The Sky train is approximately 40 kilometers (20 miles) long. Proximity to the sky train raises the rental costs, as does being a foreigner.
Virtually any area along the sky train lines will satisfy your listed criteria.
To save money you will need to evaluate available accommodations. Pay attention to pollution, noise, smell, vermin, etc. Negotiating face-to-face in a polite and respectful manner will pay off. Don’t sign a long term lease until you know you have a reasonable commute to work, services and entertainment.
Good luck.