Call sign request (User deleted account no action)

Assume this is the right place to request a CT call sign. Returning to CB after a long gap. Started back in the day just when FM become legal CB. Never used the AM band. Got hold of a President Grant II but live in a top floor flat only 1 story high. Housing association with antenna restrictions. Have a 10 x 5 metre loft above me but as back of building roof slopes down very rapidly, so high spot loft space start at a out 2m and height gets smaller very quickly. Suggestions for an antenna that I could use in this situation that people could recommend that  would pick up vertically polarized signals? I also wonder if there would be enough CB users close enough for me to talk to on a compromised antenna.