Has anyone in the uk had problems with northwood estate agents in worcester?

my son has had huge problems with these people.he and his fiance went for a house to rent with them. after taking 200 quid for checks, etc,they now say they need a gaurantor despite both being in full time employment and earning a bloody good wage between them. northwood now say they will need a gaurantor for any property they go for, and, after seeking legal advice, i have found out this is incorrect, so i wondered if anyone had had similar problems with them or any other estate agents. are they just taking advantage because they are young or just cheating to get their money, or, am i just old and cynical?????