How much is it currently costing you to have your accountant do everything? Are we talking more like €100-200 or several hundred Euros?

The 720 costs around €180 to €240 depending on the amount of work they have to do. As its hopefully a one time thing thats Ok for me.
Standard tax returns for the pair of us is €120. Which to me is not bad seeing as the accountant in the Uk we used for our personal and the business returns (including vat) worked out around £800 a year.

The company I use have so far helped us with NIE, Residency, Driving Licence exchange, buying the flat, Non res tax returns and they are available at any time if I have questions. I will use them to do our wills when we decide to do them.
And once here five years we will use them for our permanent residency stuff.

Don't know if the figures are expensive but Im happy with them as my level of spanish is not high enough yet to consider doing them myself.

I decided to throw caution to the winds and have a go at doing my first ever Modelo 720, as it is a very simple one involving only two bank accounts. I'd worked out the closing balances and average quarterly balance for the final quarter of 2023 in advance, and got together all the other information required, having read everything I could find about what was needed. Being extra careful to input everything correctly, and pressing the validate key to look for anything I might have missed before confirming, signing and sending, it took just over 20 minutes.

I did the same Lynn 4 years ago . Last year I had to remove one ISA account as the interest was so poor. You just go back into your record and close it. I have to add the new account I opened this year. Its not difficult to do yourself as can be done in English. So long as one pays tax on interest or profit I can't see the issue.

Thanks, Bob. I know I will have to do an additional one next year as I intend to open a new offshore account very shortly (my current savings account only pays a decent rate of interest up to a certain level and then it drops by almost half - always seems the wrong way round to me, as I'd expect a higher interest rate to be paid on a larger balance, but it is what it is). I guess by adding the new account and amending the balance in the existing account AEAT will be able to see where the money in the new account came from (the difference will be more than €20k), As you say, as I've always declared the interest on my account and paid Spanish tax on it, I can't see an issue either. I quite like learning how to do something new anyway.

I do both the Modelo 720 and Declaración de la Renta myself.

The argument that it's penny-wise and pound-foolish to do Modelo 720 or the Declaración de la Renta yourself doesn't necessarily hold true, in my opinion.

When you use a gestor/abogado etc instead of doing it yourself, you are making the assumption that they will do a good job. That's a pretty big assumption to make in Spain.
If you have a solid recommendation from a trusted source, then it would make sense, otherwise beware.

I asked some basic financial questions to more than one abogado with a good reputation (e.g. treatment of ISA / equalisation payment accounting) and their answers showed that they had no idea.
If you employ one, they'll send through a questionaire for you to fill in....which is basically the same questionaire that'd you be filling in directly on the Hacienda website anyway.
Then they just copy and paste it (or their interns do maybe....)

DIY is the way to do it, but if you're not comfortable with computers and/or personal finance, finding a family member or close friend who is, may be a good alternative.