Why anyone will rent an account if he can buy with the 4 weeks of rent amount ??
What if the person posts spams and got banned or got banned because of spams posted in the past ??
To answer your second question if a person spams, op can just default on the loan and get the 0.3. He'll probably make a rule about it.
For your first reason, I agree with it but sometimes I guess people want to sign up for signature campaign and maybe do some trades at a sr.member so people will take them more seriously.
But OP yeah I suggest you sell the account. How much are you thinking it will cost? I am curious.