I am fixing to have a trailer built (next week). My options are 6.5x14. I priced a single for $855 and a tandem axle for $1075. I would prefer to have the single and may just get it 13foot long. Am I gonna make a mistake by doing this. The axle is 3500. Also this trailer was priced with a side a rear gate. The side gate will be 42 inches wide, I wanna try to get it 48" wide though. He said the wider the side gate the more it will angle down towards that side or something like that. Currently I have a 60" super z and plan on purchasing a walk behind this year. That is when the side gate will come in handy. Any advice and help would be great.