I'm Edith01 and I'm getting started as a translator from Spanish to English
The first question has to be are you an English to Italian translator (as the first pair quoted on your profile suggests, and would seem logical), or a Spanish to English translator? It may not be pertinent to your post but it certainly seems pertinent to your career.
I'm seeking advice on a business matter:
1) I need to prepare an invoice and I'm not sure how to go by it. I believe the tax rate in Spain is 21% VAT and I was wondering if anyone could help.
Are you set up as an autonomo in Spain? (Sorry, I never know which "o" has the accent so I'd rather leave it out.) If not, what is your current set-up?
Are you invoicing a Spanish client or one elsewhere in the EU, or one outside of the EU?
If it's a client within the EU, are both you and the client registered for VAT?
If it's a Spanish client, is it a registered business, meaning you have to deduct IRPF?
2) I've been asked to proofread some work and I would like to know what is a sensible price to ask for this type of service.
The normal way to quote for proofreading is by the hour, as you never know how long n words will take. I would certainly never quote a per-word rate unless I'd seen the entire text and examined it closely at random points throughout (in case 2+ people had worked on it). Your hourly rate would normally be the same as you charge for spending one hour translating. So, if you charge €0.10 per word and you translate about 250 words per hour, then your hourly rate would normally be +/- €25.