Hi Tony,
I personally think that Vedado would be the best place for a casa in Havana. The second best would probably be Central Havana.
I have a nice writeup about the difference between Vedado and Old Havana here: https://bestcubaguide.com/old-havana-vs-vedado-which-to-choose/
There is also an article here detailing why I think Vedado is the place to rent in. https://bestcubaguide.com/cheap-casas-particulares-havana-cuba/why-vedado-is-the-best-neighborhood-to-rent-a-casa-particular/
I have many good places listed on my website. You can see the casas in Vedado and Central Havana here: https://bestcubaguide.com/cheap-casas-particulares-havana-cuba/
Basically, I think you are best off getting off a main road, as those can be very noisy and dirty. A side street with a nice balcony overlooking a quiet street is best. In Old Havana, there are some casas that overlook the main streets where all the tourists walk down. But those casas are usually very noisy and dirty. It is best to go a little bit out of the tourist area for renting a nice casas.
If you have more questions, just ask.
Take care,
Mario
