Job at real estate firm halal?

I have been offered a strategy job in a multinational commercial real estate firm . The firm deals in everything including construction, facilities management, leasing , producing land , financing etc. Though my job is totally in another division and has nothing to do with mortgage, but is it halal to work in this company considering they do advise companies on mortgage lending etc. But they offer many other services and again my job is in a totally different department and has nothing to do with financing. Kindly guide me as I have to make a decision asap.
Thank you for your time.