I bought tubeless wheels from Hunt and had them fit tubeless tyres. I've since changed the rear and had no problems fitting it tubeless, using the existing rim tape. I then had wheels built with Mavic tubeless rims and set them up tubeless myself. One tyre was no problem, the other required a tape re-wrap after damaging the tape fitting the tyre, which was particularly tight. I then converted the wheels on my electric bike to tubeless. It had come with tubeless rims and tyres, but fitted with tubes and non-tubeless tape. No problems doing these wheels.
Setting up the wheels is not difficult - it just takes time and patience to get the tape wrapped correctly. It get easier the more you do it. Some tyres are easier to do than others, ditto rims. I've not yet had a puncture that I'm aware of on any of these tubeless wheels.