Lease and MOU dues of a partner in 2 firms

1. A part of an industrial shed at Peenya industrial estate Bangalore was rented/ leased to a person (MVK) since around 2006 in the capacity as Partner of a firm (HPE). HPE does not appear to be functional now, but not sure as it has moved to some other location around 2013-14. There were dues accrued over a period which were summarised in agreement executed by him (MVK, while HPE moved out) as an MOU in 2014 (attached). His wife who works as a Professor in a Government University gave additional guarantor assurance in the MOU, a reason why we continued the relationship. This liability is Rs.3,21,000 plus a Promissory Note he signed for Rs. 1 Lakh earlier for borrowing a full set of tools from us and a crane attachment (which were never returned to us despite repeated requests). 2. MVK joined into partnership with another 2 persons (R and M) under a firm called MM and entered into a fresh lease in April 2014. But again the party has defaulted and has accumulated dues amounting to Rs.1,05,000 as on 30th September 2015. The party also opened the door between the two portions and kept some of their project stuff into our part, so there was no locked barrier between the 2 parts since about September-October 2014. As per the agreement they signed, there is extra rent payable (@Rs.25/SFT) for the extra space in which they have kept their material which amounts to Rs. 2,05,000. So the total outstanding dues after adjustments of security deposit and amounts paid by them as on 30 Sept 2015 stands at Rs.5,81,000. We got fed up as after repeated reminders and requests also they did not pay the arrears and did not fulfill their obligation of paying up arrears as well as BWSSB accrued bill which brought an emergency of disconnection of Sewerage line in September end, so we have locked their entry from the back door, from inside, about 10 days back. Their/ their client's assets are in the premises. They are now contacting/ trying to settle, but we suspect from their tone of communication that they have no plans to pay anything to us but just show the carrot of payment and move their assets out once the back door is opened. We have drafted a "without prejudice" email to the party which comprises details of dues and amounts paid by them. Scans of lease agreement and MOU and promissory Note can be sent for ready reference if a lawyer/firm is ready to help us further on this. Kindly provide preliminary advice online or by email based on info above and let me know whether any competent lawyer is interested to assist us and the fees involved. We would prefer a Contingent Fee basis arrangement.