Rotavators

Evening, 

I bought a small holding two years ago and have been very busy, but now the time has come to start looking at growing some veggies. Im getting a Polly Tunnel but currently looking at a way to make the soil suitable for planting. 

I've let the pigs churn up all the soil in one of the fields and the result is a lot of mud. So I was thinking of investing in a rotator / tiller to attempt to make the beds suitable for planting in. 

Has anyone got any advice on these and what I should look out for / consider? Or is my thinking totally off? 

Thanks

Denis