iker well carryingmoney is always a problem make sure u have a safe bag u carry round u r neck. Iran is quite safe not much mugging goes on. If hotel has a safe then use it.

hi i was in iran for 9 days and i spend a total of 210 pound sterling and that was inclusive of a flight ticket that i bought from shiraz to dubai for 65 pounds.
i got by with staying in hostels and also eating mosty street food which is cheap and hot. they have guys selling stuff like aubergine stew which is great and costs only 10,000 rial in the cities and the same dish costs abt 4000 rial in small towns. also kebabs are not all that expensive. also nearly everywhere there are bakeries producing hot bread and thats cheap too.
i go by the idea that if something is really hot , it should be safe even by the road side and if they are many ppl eating there and it is a crowded shop than i will eat there. i only went to proper restaurants twice , wish i had done more actually as the experience is great, the food and the people watching you can do.
travelling by train is also cheaper than bus and it is probably more comfortable. my sleeping compartment in the train is half of the bus fare from kashan to yazd so try to use the train if possible. the travelling times may be weird though but a lot cheaper than buses. i didnt find the buses all that comfy anyway.
with that budget i even managed to stay at a nice hotel in esfahan, iran hotel. the hotel itself was great , breakfast was good and the guys at reception were very helpful.
have fun
venga