Iran Experience
 

I've recently been in Iran for about a month, people were really kind and hospitable but I had a lot of problems with Iranian currency and also exchanging rate was very complicated. I have a suggestion for those want to enjoy their trip to buy tourists debit card in advance to their trip much more enjoyable without any stress of running out of their cash!

Not sure what a "tourists debit card" is. Int'l ATM/debit cards don't work in Iran because of the sanctions.

We were in Iran 2 or 3 years ago, and we had no problem exchanging money. Our guide took us to the exchange streets and it was smooth.

You are right everything had changed. these days exchange rate changes a lot, even 2 or 3 times a day, It was really hard for me to check the price before all payments, and sometimes specially in far areas it was somehow impossible to do so.
I didn't know about tourist cards then but when I returned home one of my friends told me about Daricpay and another tourist cards which you can buy them in advance and use them as a national debit card. I'll definitely try them for my next trip.

I was in Iran in December, and had no trouble changing money. I just walked around with cash on me. No problem.

Just avoid the touts at the airport as they want you to change money at the 'bank rate' which is less than half as much as the street rate.