Parking on Common Property
If you believe a vehicle has parked on common property in breach of a by-law (e.g the standard section 2 by-law regarding vehicles) you can make a complaint with the Council of the Strata Company who can issue a warning or a breach notice to the owner of the offending vehicle.

Extended parking in a visitors bay
A visitors bay is part of the common property of your building and it is safest to assume it is dedicated to temporary visitors only. If you believe someone in your complex is using the bays for any other purpose, you can make a complaint with the Council of the Strata Company who can investigate the matter further.

Someone has parked in my bay!
If you believe someone else has parked in your part lot bay (e.g your allocated car parking bay) this is deemed to be a private issue as the Strata Company has no jurisdiction over your car bay. In the first instance, if you don't know the owner of the vehicle, you can leave a note on the car. Failing this, you can request a letter to be sent to all residents about vehicles parking in the correct parking bay.

A vehicle has been abandoned
If you believe a vehicle may have been abandoned:

• Check with the Police first on 131 444 as the vehicle may be of interest to them (e.g it was stolen)
• If the vehicle is not known to anyone in the complex and is of no interest to Police, then owners may have to apply to dispose of the vehicle via the Disposal of Uncollected Goods Act 1970. Your strata manager may be able to assist with this.

Wheel Clamping
As from 14th December 2020, the use wheel clamps as a way of managing private property parking has been banned. Wheel clamping refers to all means of vehicle immobilisation, including wheel boots and other devices such as Barnacles, which attach to a vehicle's windscreen.

The below is a standard by-law

Schedule 2, 1. Vehicles
A proprietor, occupier, or other resident of a lot shall not park or stand any motor or other vehicle upon common property except with the written approval of the strata company. 

https://www.legislation.wa.gov.au/legislation/statutes.nsf/law_a226.html 

Example story

A vehicle is parked in the driveway of a complex making it difficult for other vehicles to pass freely. It appears that the vehicle belongs to a tenant who has 2 cars but is only one allocated car bay.

The complainant does not want to engage with the tenant so they contact the Council of the Strata Company with all the information of the complaint. The Council of the Strata Company then passed on the information and instructed the Strata Manager to send a formal letter to the Property Manager. The formal letter requested the vehicle to be removed in line with the bylaws of the strata company.

The tenant then arranged to store their second vehicle off-site and comply with the request and strata company bylaws.