The title registers held by the Land Registry are public documents. Anyone can download a copy of the title register for a particular property for £4. The title register will show, among other things, details of any charges against the property:
http://www.landregist...ortal/Property_Search
If someone owes you or your company money the first step is always to send a formal written demand for the money. (No court will consider making an order in your favour unless that has been done). The letter should clearly show the name and address of your management company, and that of the recipient. It must also be dated and leave it no doubt that it is a formal demand for payment. (Actually heading the letter 'Demand for Payment' is a good idea). Further it should clearly indicate that if payment is not received within a specified period (I suggest 21 days) legal action will be initiated against the debtor.
If payment is not forthcoming within the specified period, commence legal action. The simplest way to do so is to use Her Majesty's Courts Service's online system:
http://tinyurl.com/5kwx6
Chris