I have a full thieves guild and highest master level and 8 guys with pistols fully trained, but the only building that i am able to attack is the guard house. Is there something wrong with that? i took over the guard house and i want to attack other buildings but i cant select any others even when i have 100% recon...? Help please...

you can only attack buildings that has troops like you (thieves, robbers, guards, mines, ...).