I suppose this is my area, or my area for my area.
Don’t want to be cryptic or difficult, but it depends on:
Which area of Spain you are looking in.
It also depends which type of property you buy, you say resale but the vendors of same can be multi-various these days; private vendors, bank repossessions, finished developer units sold on for previous investors and they may have different rates.
And then, well it depends of course on the “Agent” are they a real agent like say – Fuengi – who is on this forum quite a bit, I understand has a real office, website and genuine listings or, are you going with some Back Bedroom Agent who has an alluring website, supposed 50 years combined experience and no listings but all the “know, you gonnna need mate” you won’t have a clue there, the Vendor may be paying up to 20%.
As long as you do your research correctly, as long as you get a clear idea of property values in your preferred area, you need to work on the actual Selling Price to you, plus Costs. And compare this with what else is available.
But, in my area, the genuine Estate Agents, I would say like Fuengi will probably charge 5% and for good historical, logical and financial reasons, so please look at other threads as to why not 1% like the UK, you need to think of the USA and almost everywhere else being the same 5% and the UK being kind of unique. But the argument has been had elsewhere on the forum, more than once!
Also consider that in my area the Costa del Sol, the reputable agents, the ones who actually do list genuine private vendor resales will also mostly share their listings and so be recieving usually a 2.5% fee being a split commission from Vendors.
Get yourself a real agent, and don’t be too worried about the commission is my advice, a real agent wants good business from you in Referrals for the future, and will always look after you, but now picking that agent…. mmm, you will get some better advice from others than me on that one.
Hope that helps.