I'm offering this to give some ideas of what can be done if the need arises say for a Hurricane evacuation.
Sometimes people need to haul things that just do not fit inside their BOV. I sometimes need to take a bike along, and it will not fit inside the Suburban.
Oh Hi; time for a bike rack. There are choices for racks roof mount or hitch mount. The Suburban has a roof rack, and I do not want to fight my way past a hitch mount to put groceries in the back of the truck. The factory roof rack has sturdy rails but the cross bars are barely sturdy enough to tie string to.
There are some companies that make good looking high quality roof racks, and fittings to carry; bikes, skis, canoes, cargo, etc. I like them but for now the out of pocket expense is a no go.
I did have a bike rack that I got cheap from Craigslist that only needed to be attached to the roof rack on the Suburban. Now to review my comment about the weak crossbars; really not able to securely carry a bike.
Oh Hi; we're going to Home Depot. Now for about 30 dollars of hardware I have a WECSOG roof rack that I can use until I find a screaming deal for a name brand rack, and is sturdier than the factory.
First I need better crossbars. Conduit fills the need at a reasonable cost; under $10 for a 10 foot section. I cut the 10 foot piece into the desired length bars.
$10 conduit subing for $75 corssbars
Then I gotta attach the conduit; 8 Ubolts.
$10 of Ubolts subbing for a $160 set of name brand adapters
Next install the name brand bike rack. At this time I could have used the rack as designed, but I added some hardware so the rack would be sturdier than originally marketed. 2 Ubolts, some unistrut type angle, 3 bolts another $10.
Here is the rack installed and stowed.
Test the system.
This works well for me because this rack will haul any size bike without needing to take off a wheel. It is called an AnkleBiter, and is no longer in production, but is available used.
I saw a Clampit roof rack at the hardware store made of 2x4 lumber lashed onto a factory roof rack with ratcheting tie down straps.