$3k? I’m not an expert and I don’t own a shop but I would imagine 15+ hours for the install. Probably more like 20. Times that by a shop rate to get your $$$.
i'd say that's a fair assessment time and money wise for a tidy install: cleaning and painting stuff, getting it set up to a decent spec, maybe dealing with whatever small problem or two might come up: rerouting a brake or fuel line type of thing.