I made my own, but only because I couldn't configure boxed (store bought) cabs. in the way I wanted my lq laid out.

If you go with boxed, you'll find that uppers are a good depth to use as base cabs. as they are shallower (front to rear) than traditional base cabs.  They won't have the toe kick, but that is simple enough to build out of 1" x 4" stock.  Also, the countertop will have to be custom, but that's easy enough to do now with MDF, good adhesive, sheet laminate and an old rolling pin.

Are cabinets as hard to make as I am imagining??? I know I will either have to learn (or teach hubby) or hire someone because of the angles in our trailer (nose narrows slightly, walls kinda 'taper' at corners, etc).

The countertop was going to be my next question.

Can those "pre-fab" countertops they sell @ Lowe's or Home Depot be cut to make them more narrow (front to back) as well as make them shorter?

They have one that is 4ft long, but I didn't measure it's depth (it looked pretty wide). I need one that is 38". The 48" pre-made one is only $34. My counter here at the house is only 24" deep (OLD house) but I'm pretty sure the one at the store today looked a good bit wider.

Once you've done it a few times, cabinets are fairly easy.  The first time is quite intimidating, but really, it's just a box with a pretty face.  Drawers are tedious for me, so we don't have any.  

If you hire out, those tricky angles shoudn't be too much of a challenge for any competent cabinet maker.  I've never put cabinets into a house that wasn't out of square - scribing is a way of life.

Yes, you can cut down that counter top you found, but you'll be cutting off your backsplash.  With care, you may be able to salvage enough material from what you cut off to fab a backsplash, but it may be easier overall to just make one.  It'll cost more than $34, but you will have the sense of accomplishment and a truly custom countertop. 

Laminate & mdf are easy products to work with.  Once you get the hang of it, you'll be putting new countertops in every room of the house.

I know there'll be some with differing opinions on this, but when going with pre-made cabinets, it may be worth while considering all wood as opposed to particle board cabinets.  All wood such as pine will be a bit lighter in weight than particle board in case weight is a consideration for you and all wood will hold up better under the vibrations and movement of a horse trailer as opposed to a motor home which has much better suspension.  IMO...

Also, when purchasing pre-made cabinets, consider bathroom cabinets rather than kitchen.  You will be able to find them in sizes not as deep as kitchen cabinets which may fit in your LQ better.

You do really nice work. Do you have any pictures of your finished trailer???

I found some really good deals @ Lowe's on solid wood (Oak) ready to finish cabinets. I just have to get outside and see how/if they will fit where I want them.

The other issue is the nose cabinets. They aren't a must, but I really want all the storage I can get. Those will definitely have to be made because our nose slopes in at the sides (damn aerodynamics!!!).

The construction of traditional raised panel doors, involves the collective efforts of many expensive tools. It is not economically feasible to try to save any money, by purchasing these tools and trying to fabricate one set of cabinets for a LQ. It is much more cost effective to purchase the doors from any number of sources. The boxes and face frames are less involved and need more simple tools to construct.

Many of these tools are very powerful, and without proper training, can easily cause major injuries. There is a significant learning curve with wood working tools, and those without any knowledge, should take courses in their operation before attempting these projects.

Woodworking is a wonderful business/hobby/pastime. However, there are many experts missing body parts, and all can relate their favourite time, of how they were quickly hurt by making a simple mistake.

BOL  Gard