We are trying to buy a house but had paid landlords with money orders which we can not find the records ,and have requested a letter from landlord as to what we were paying and they refuse due to not wanting to buy there house what do we do.

You had better start keeping better records. Post office or bank has copy of money orders, whichever one you used.

What do you mean, 'you are trying to buy a house' ? Do you mean rent/to own ?