I used to live in Norway and have visited Oslo a few times; I find it quite boring overall. I’d rather spend (summer) time in the mountains and in the western fjords around Bergen.

Since you’ll be driving, be prepared for tolls, low speed limits, and very high traffic fines… as well as the generally high costs for just about everything.

I’ve not stayed at 3* hotels in Oslo, but I have stayed at 2* City Hotel, and at the MS Innvik b&b. The Innvik is kewl—moored in Oslo harbor with a wonderful breakfast included, ensuite rooms with dated decor. City Hotel is aptly named, a bit nicer than Innvik but with shared WCs and showers on each corridor. Parking for both can be pricey.

Thanks Don !
Indeed, parking is another issue I’m trying to solve.