I try to answer.
From Alsace, at least three the routes to get to the Lake Garda area.
1. Via Basel, Lucerne, Gotthard tunnel (17km not recommended for those who suffer from claustrophobia), Bellinzona, Chiasso (Italian border). Then Milan, Bergamo, Brescia and finally Desenzano or Peschiera.
Requires Swiss vignette for vehicles under 3.5 tons (about €40) or purchase (at the border) of a certain number of days for those over.
530Km. Advantage, as soon as you pass Italian customs you are five kilometers from Lake Como.
Good stopover at GPS 45.83510, 9.06067 but it is not very large (10 seats) and could be full.
The town of Cernobbio is 1.5km away. From there possible boat trips even to the northernmost part of the lake.
2. Via Basel, Bad Ragaz, Chur, Bellinzona, Chiasso. 615Km. Same comments as above.
3. Longer (700km) via Basel, Zurich, Innsbruck (A) and Brenner Pass.
Requires Austrian vignette for vehicles under 3.5 tons and Go-Box (kind of electronic toll tag) for those over.
Plus the payment of the Europabrücke before the Italian border.
Advantage, the possibility of some visits to the beautiful Dolomites region.
Two lakes. Both beautiful but different in size and orography.
Lake Como is surrounded by mountains that plunge down. So there are few possibilities for stopovers.
Good road up to Argegno. Continuing north rather narrow, to be traveled with caution.
There are campsites but only in the northernmost part of the lake.
I would avoid the road from Como to Bellagio as well as the eastern branch of the lake (from Lecco north, almost completely in a tunnel).
Lake Garda is different, at least on its eastern coast (towards Veneto).
If you want to venture on the western one, no problem up to Salò. I would avoid continuing further (narrow, tunnels).
Between the two lakes you find a third, Iseo.
Nice, just be careful, if you want to get to Lovere go along the eastern coast.
The western road is good up to a few kilometers from this location.
Then it becomes very narrow and problematic even for a PVC.
Stopovers: Park4night (
https://park4night.com/en ) is pretty accurate.
You can apply filters for the type you want (camping sites, free or paid areas, at farms, etc.).
The only caveat is that it is also oriented to small vans.
Check the reviews carefully and maybe take a look at the place using Google Earth and also Street View.
Austrian Tolls:
https://www.asfinag.at/en/ , homepage and subpages you will find all the information. Basically with a vehicle under 3.5 tons you only need the vignette (sticker, purchasable at the border or in some service before arriving there or electronic stickerless).
The vignette can be purchased with a validity of 10 days, two months or year.
The Go-Box is only needed for vehicles over 3.5 tons.
In Austria there is also a "pollution sticker" but it is only required for commercial vehicles (category N1, N2, etc.).
Since motorhomes are category M1, they are exempt.
Swiss Tolls (how they work):
https://vignetteswitzerland.com/switzerland-motorhome-toll/
Max
p.s. Lazise not Lizaise
behind the park up to a huge eagle monument to the Swiss army that protected the pass during world war two....Great for few photo's...there is toilets beside the park up,fresh water and grey/black dump...I heard recently there's a cable car ride that can be done with savage views of lake garda,it's about an hour or so drive from peschiera, I might check that out this time round.
