For your Grand Design Transcend 29TBS the slide topper I recommend for your 118 inch flange to flange measurement is the Solera 10.5' Slider (Slide-Topper) in Black w/ Black Hardware # LCV000182037. This slide topper is designed for a box width from flange to flange of 116 to 121-3/4 inches. This will fit your slide out perfectly.
It is also available in white with white hardware # LCV000163293. These awnings come with all the awning rail included. view full answer...
While your Grand Design Imagine 21BHE is lighter weight it does weigh more than half the weight of your tow vehicle so a weight distribution system will be a great idea and I would recommend you go with one. You'll have better ride quality, handling, and braking so it will be worth it. Based on the weights you mentioned the Fastway kit you are wanting part # FA94-00-0800 would work really well so that would be a solid choice as well. view full answer...
Based on your 2020 Grand Design Transcent 265BH's current # TREQ104 equalizers and 33" wheelbase I recommend going with the MORryde CRE3000, as in my opinion it's a better design of an equalizer that does a better job of preventing bumpiness going from the road to the trailer than the Dexter EZ-Flex.
For your trailer you'll need the following components:
MORryde Rubber Equalizers # MR87ZR
MORryde Suspension Upgrade Kit # MR58ZR
This is not too bad to install yourself assuming you have... view full answer...