I would look at as many examples as you can find, pull the parts you really like from each together, and then probably have an attorney review it as a final step.
It should save you $ versus paying them to start from scratch, and they may catch something that would be disallowed in your state. Pay for an attorney's time when you have very specific and focused questions you need them to address, never for anything you can prep yourself is my feeling...
I am guessing that the generic one is impartial or possibly too strong on the tenant's side. I would go for the strongest one allowed by state law in favor of your rights as a landlord.