The house CAN sell with the judgment liens on it but they will remain as a cloud on the title until they're paid and a Release of Judgment is filed with the Register of Deeds.

One other thought I forgot to mention for you specifically would be to make sure they are using cloud/web based property management software.  

I personally would only deal with licensed agent and close with title company for them to do title search and grant GW deed so that if there is clouded title or liens on properties the owner or bank will pay it.  

Using a Mac-specific or Windows-specific app is more likely to lock your data down to a specific machine, whereas a cloud-based application can be accessed from anywhere, and probably has tie-ins with other services/products you could use due to the nature of their design/environment.

I was wondering if anyone has specific experience with different website templates, either the ones included on the different software programs or just wordpress or another CMS platform in general that they are happy with and would reccomend.I found this list  http://www.biggerpockets.com/rei/online-property-management-software-cloud/ very helpful for the different property management software options out there, some of them include webstie option, but Im not sure how great the functionality goes without trying all of them, so i thought I would reach out here first. 

I can recommend Brian Cloud of Cloud & Willis.Ralph

You can record a memo of your contract, creating a "cloud" that may prevent him from selling.  

I am with Chase Real Estate out of Naperville and our brokerage specializes in investment properties.

We use Google for everything... email, web hosting, cloud, etc.

You can't force the owner to sell to you, but you can cloud the title.