If you have a years lease with the tenant YOU will have to PAY HIM to move...thats what you sign a lease for, to prevent a landlord from screwing with you....
As far as the other stuff.....unless it is in the lease, how can you prove he removed lanscaping? did you take any pictures? He will deny it of course......
Redecorated HOW? Painted? well that you take out of the security when the lease is up.
added walls or partitions, if its temporary, then not much yu can do, but if it is permenatnly attached to the house, then it could be a violation of the lease.
Changed locks...well you did move to another state,and if you wanted to inspect the house you should call first anyway and give the tenat notice that you were coming over before you left the other state... and who knows if the last tenant still has keys....
so you need to explain your situation better.....before he gets a lawyer and sues you for breaking the lease.