Interesting. Seems you’re getting a bargain :-)
http://www.upc.ch/en/tools/basic-digital-offer/
The connection fee is just under Fr.34 a month (it sneakily goes up quite regularly) and if you rent it’s usually paid in the monthly service fees (called “Nebenkosten”). This means that a Cablecom package costing Fr.99 a month actually costs Fr.133.
If, for whatever reason, your landlord isn’t paying the connection fee on your behalf (and billing you in the Nebenkosten) then Cablecom will bill you directly. Make sure you’re not being charged for this twice by mistake! However, why yours is “only” Fr.29.45 I don’t know. Maybe it’s sometthing else entirely, although I can’t think what.