We have floor rollers fitted in all our vans and they come out of the back of it , I wouldn’t want to work leaving doors open on the vans , should there be any wind they blow shut , and if anything is stolen your insurance will be invalid as it’s left open , I know some have hoses out of side doors but all the ones I have seen cause an awful trip hazard due to the height the hose comes out at , personally think having it through the floor is the best option