Replying to Drop in +k

so  i am looking for quick replies and the build a jib can take a while to get a reply in. so im a building a summer setup and have a few questions
1 im going to be using scaffolding for my drop in becuz i have some not being used so should i make it 5ft or 10ft tall
2what should the top material be could i use carpet or is it worth trying to get astro turf should i put orange fencing over top either of them
3what should i use to lubricate the top material
4what angle should the dropin be at
plus k for real answers