I have been to Cuba 8 times but not to Havana. I love it !!I was last there in February to Cayo Santa Maria. We exchanged our Cdn dollars to the convertible peso. We have tipped both money and items . Everyday we left a bag for housekeeping , toothpaste, toothbrushes, shampoo, combs, brushes, anything for the hair, baby items , school supplies, colouring books ,etc. chocolate bars, gum, candy, makeup, nail polish. Honestly , you name it , they need it .
The people are wonderful and very welcoming. They are talented, intelligent people . They love their music and boy can they dance .
For us its been very affordable but prices are going up and more hotels going up since the embargo has been lifted.
I have a friend who goes to Havana all the time . If you like I can have her contact you and she can be more specific.
We have rented a jeep with no problem to tour the countryside and some of the towns. American credit cards were never accepted but I'm sure that will change.
As for food . It depends on your expectations. I never had any problems with choice or quality.
Planning another trip to Cuba next spring. As suggested , check out Trip Advisor.