I think it would be beneficial to new members if they had an option to purchase alliance buildings. It takes so long for a hospital to complete full expansion level.
With main admin approval to sell it I believe this is something that should be looked into.
The new member would request to purchase said hospital, prison(but it would be transformed into a jail after purchased) or school.
The admin would have to control this sale the funds used to purchase said building would then go into the aliance funds. I do not see a way to do this via coins.
after posting thoughts.
They also would be able to sell it back to the alliance for full refund with approval of admin again.