Going to Barcelona in late October. Will leave the USA from Charlotte unless I can find a cheaper flight through Dulles I will plan a stop or two in between to get to Istanbul to meet up with friends. Istanbul back to Barcelona. Then a week later the reverse.

Can I get some advice on:

A) where to stay? Would prefer the city not the beach.

B): any airlines to avoid?  Been to Europe several times and flown on different ones.

C) advice on what to see or do?

D) what to avoid?

To answer questions before you ask.. I used to enjoy cheap trips to Europe, I know this one won't be. My friend is Russian and will bring her teenage son. We are both divorced. Met decades ago. She teaches languages including Spanish., Portuguese etc. I speak a littlle of different languages. Basically the trip is centered around the sons holiday at the language school there.

Point me in the right direction. I want to thank everyone for the prior responses

Update: I apologize for the destination change. She has lived in Europe before (not Spain)  but western Europe. We would have had to gone to another country she lived in and applied then wait for the visa to be approved in transit. Had 10-12 days but it didn't work out on Spain this time. So we are staying in Turkey, Istanbul and Cappadocia.

Kind Sir, thank you!

Well familiar with Gypsies/Roma,  from prior trips to different places in Europe. They unfortunately seem to be everywhere. Also she lived in Mexico City a couple of years, and is from Moscow so used to large cities.

Planning to stay in the city not beachfront. Prices mostly. Looking at business class hotels.

Anyone ever been to Istanbul? I've never been, but it seems like the best idea to pick them up. Other countries like Armenia, Qatar, Israel etc don't seem like a better option right now. Not knocking Israel, just the conflict.

Went there Jan of 23 and had a great time.
Stayed at the ICON Barcelona , great hotel in a decent location. I wish we would have stayed closer to the gothic quarter. It's all very walkable, just stick to the larger streets and you'll be fine.
You have to see the Baslica de la Sagrada Famlia, one of the most impressive things there.

We took a day trip to Girona and it was amazing, highly recommend it. It's an easy train ride from Barcelona-Sants station.
Cheers

Thanks everyone for the replies, bearacracy came up so we had to change destinations. See OP