travel tips from Belize to Granada by boat/bus (Managua)

Hello,

I am a Peace Corps Volunteer, just finished my assignment, and am planning on visiting Nicaragua to consider it as a place to semi-retire. I am an arts administrator/teacher who worked on a national literacy program here in Belize. I will be traveling alone and any tips on safe places to stay would be welcome. I think I can take a boat from Dangriga to San Pedro Sula and then a bus to Managua, and then a bus to Granada, but don't know good places to stay, and I have also been told not to be in Managua, or San Pedro Sula at night. Anyway, if anyone has taken the trip from Belize to Nicaragua, any advice is appreciated. I am not able to fly, unfortunately.

Thank you!!