Hiya F.
I looked into this last year for our 25th wedding anniversary, but ill health stopped us from booking and also recently for my hubby's forthcoming 65th birthday next month.
If you are thinking of visiting Sevilla during semana santa (holy week) which our wedding anniversary usually falls within, then you really have to book very early and the prices rocket for that week.
We wanted to do the Andalucian jewel tour with Cosmos Tourama as it is many years since I was last in Sevilla and Granada, however, I'll be quite truthful and say that the 8 day tour price put us off, we decided for a bit more money that doing the whole tour of Spain in 15 days would be a better option for us...might as well burn the whole lot in one go
I know that Cosmos have the option to tag another week onto the 8 day tour, but the hotels they are using are not ones that I particularly would want to stay in....not because of the hotels, but because I don't want to stay in Benalmadena although Mijas is one of the options, but then you would need either a car or to use public transport to get around the immediate area.
Cosmos and Archers seem to have a monopoly on the UK market and I did find another site, but guess what ? it lead back to Cosmos and whilst it was basically saying they were cheaper than Cosmos, when the final amount was totalled up, they were in actual fact, NOT!.

If you look in the Sunday supplements of papers like The Times and The Telegraph, then they advertise from time to time.

Here is one such advertisement from Riviera Travel with a contact number to request a brochure. click here
Here's Travelsphere...I just threw a wild date into their search engine and have not looked at the itinerary to note which cities are on the list...there are other tours on the next page and a difference in price.
Finally, one thing about the particular link from Travelsphere that I have posted, is that the price includes Half board....if you find a deal with Cosmos or Archers including half board, then pm me.
Most were including 4 breakfast and 3 evening meals, so you need to take into consideration the extra meals that you will have to buy.
click here

My friend who started out as my Spanish teacher, she (and hubby) did the Andalusian jewel tour last April, ironically for their 25th anniversary with Cosmos Tourama.
She was well impressed with the knowledge that the guide had, and she knows her stuff about Spain.
To be an official guide that is recognised by the Spanish Tourist Board and the various government departments is something like a London cab driver having the knowledge of every street in London.....it isn't easy to become an official guide of Spain.

HTH's
Sanjiiiiiiiiiiiiiii