Hi people

I recently went to go and view a 2008 golf R32 with 59,000 Miles on the clock. Now the car has had 6 owners!? Does that seem fishy to some people?
The car does have full service history some VW and some VW specialist, now in the service book the tooth belt box is ticked on 3 of the services...what is a tooth belt?
The bloke has only owned this car 6 months and says the bloke before him said he changed the belt...I aint risking it is there anyway i can see if its been changed?
Also this bloke has fitted a aftermarket alarm system Clifford, now the alarm system allows him to start the car while he's sitting in he's house via he's key fob! ( pretty cool ) Looking through the paperworks i come to an invoice for £900 which was ECU change and ignition switch.
Does anyone think this would relate back to the alarm system been installed to be able to start the car up?
Would really appreciate peoples feedback on this
Thankyou