I had the same problem deciding. After looking at all the makes, I picked Wells Cargo. For the simple reason of build quality. Yes they are more expensive than the rest but I feel that the extra cost was well worth it.
When looking at trailers, I noticed a big ride/towing difference with the type of suspension. The Wells' has a softer less bouncy ride because it does not use leaf springs - look at their web site, I think they show you their setup. Also, a interesting point... I sold mine a year later for $300 less than what I bought it for. So, I think that maintaining a higher resale is just as important factor as the bottom line price.:think Don't be afraid of the inital cost, like I was, because you will get that money back if you sell - I am sure.
I had a 7x14 and had build custom cabinets, a worktop with a sink and a toilet enclosure (using a chemical toilet). A lot better than using the stinky blue houses that's for sure. I only put one bike in mine but I think you will have room for three - even with the cabinets. But remember there is always more crap that you bring than necessary - so that too takes up room as well. Make sure you get the 6 foot ceiling and diamond plate front. Even if you have to wait for it to be special ordered. These alone are worth the money! Also keep in mind that the white color is easier to maintain, generic yes, but easier to maintain. Mine was black - nice, but showed every scratch. I had a hard time washing it without scratching it.
One last thing, in my experience, the ramp gate is a waste of money at a big cost of weight gain. Do without - carry a standard ramp - the deck height is not that high anyway. Oh, and it does get slippery with mud on it which is good for atleast one ACL injury... I've seen two people so far take hard falls on their ramp (riding boot soles, mud and wood don't mix) One put kitchen linoelium on their ramp. What were they thinking?
These are my opinions. Hope I was somewhat of a help.