Several modifications to address common issues in the reviews for this greenhouse. I bought it knowing there are problems and worked through them.
See the review 8 months later at https://www.youtube.com/watch?v=wLe1cZ20iZQ
This is a 10x26 polytunnel greenhouse available on Amazon for a bit over $200. I added a couple pieces of half inch EMT and 6 short t-posts. There is also some Mason line/string and 3 pieces of rebar cut and made into stakes.
I used cord/string on this and found that after a year it rots away. I have since switched to using fencing wire in hopes that it will last longer.
The greenhouse is https://smile.amazon.com/dp/B07YJK185Y
0:00 Intro
0:59 New Top Rail
3:00 String for preventing sag
3:52 Chicken Cameo
4:05 T-Posts to hold to the ground
4:55 Midnight Rebar Stakes
5:11 Rainy Day Saggy Cover
6:13 Many Many strings and success
8:22 Making Rebar Stakes
9:07 Windy Day Test with over-cords
10:22 SNOW test!