Best brand for resale?

yes condition is the most important. Brands vary in quality even among the units produced. Winnebago has a "NAME" but I am not necessarily impressed with the unit we have. So if going to buy to resell in 1-2 years I would go with an older unti that can be had fairly cheap, put a few dollars in it such as tires tuneup etc and then use and then sell. Lots of rv's out there even late 90's can be found in good condition at reasonable prices (class A's), mid 2000 class C's are also available cheaply in a lot of cases and if it is still in good condition you can sell with little to no loss as long as it doesnt need lot $$ to get it to where it wanted for your comfort and convenience. We pait $70+K for a 1year old low mileage unit which new was in the 6 figure range, they are still selling (asking $50-60K) for same rv/type. So age will be a factor but overall condition is what you need to be concerned with. There is an article on fax travel news that many are buying rv's due to covid! In a year or 2 the market will probably be flooded with USED low mileage/usage rv's IMO so return on investments will probably take a big hit as in what you stated to begin with.