2000€ a month rent for this shop means you have to take minimum 1000€ per week, every week, just to cover the monthly rent, nothing else, no wages, electric, water, TAX, etc etc, is that possible with flowers? to cover all other expenses i would imagine somewhere in the region of 1,800€ a week, 7,200€ a month.
As things are getting tougher by the week just to get by every day would customers use little money they have left over to buy flowers?
I know their is one hell of a mark up on flowers but at even 1 cent a bunch if the customer hasn't got the money it don't matter how cheap any item is.
Are other flower shops near by? if so and you can sit outside and watch how many customers go in that shop just in one day, that might give you a good idea, if you can sit in the shop you would like to rent for 1 hour, maybe a day, put a massive bunch of flowers in the window, count the people that walk by, count the people that stop to look at the bunch of flowers just out of curiosity.
I have never had any business in Spain and wouldn't try one, i am in business in England, have been all my life, had quite a few retail shops at one time, and i know of friends that opened flower shops.....back when money was about....now they get by, but not like it used to be, when things get tough financially you have to realise certain things in the world get cut back on. Spain is no different then England in many ways...No money....No spend.
I wish you all the best should you decide to do it.