I went with an extra 18 inches because I knew I wanted the loft bed accessible without unloading. I paid $35 per trailer ft (18ft) so it was $630 dollars extra. That works out to about $210 for each 6 inches of added height. All well worth the extra money.
I custom ordered my trailer with a bunch of extras to include the paint and chrome divider in addition to the fact I have never seen a 7.5ft. tall trailer on a lot already built. Sometimes you may see 6.5 ft.or 7ft. Lark will custom build, but a lot of others will also. Typically options are from a list of à la carte options. The only thing I ordered that was not on the "list" was the two tone paint with chrome divider strip and the design on the back side with gray and white. I had to draw that for them to get exactly what I wanted.
You should be able to do the same from most of the builders out there to get exactly what you want.
Mine is 7.5 ft tall inside. Here is a pic as I drove it away from the factory in Georgia: BTW.. I used the same folks that MtDon used, but my trailer was built in Douglas , Georgia.
