Tehran cost of living

Hi all, i have an offer to work in Tehran for a couple of months. Never been to Iran, I am wondering about the general cost of living in the city.
What do you pay for an apartment? Is it safe for a european / swiss? Is there an expat community? What are the avg cost of living for food, going to dinner, taxi, public transport?
What are average working hours? What time do you guys start and end working? What kind of sports or fun activities are offered in Tehran? What is the next beach city and where?
thanks for any hints in general