Build them all, hang them all, level them all, and only then fit the doors.

Doors last, after the whole run is hung and level

This is the ordering tip worth the whole page. Cabinets should be leveled, either standing on their feet or hung on their French cleat, before doors are installed. If you attach doors first you will have to readjust them once the cabinet moves, and on a run of several cabinets the guidance is to build and set all of them up without doors, arrange and adjust the complete set, and only then fit doors as the final step. Door gaps are judged against neighbors as much as against their own cabinet, so aligning them before the neighbors exist is work you are going to redo.

Two of the three mounting options depend entirely on the wall

Cabinets can stand on all four feet, on the two front feet only, or float off the ground with no feet at all. The floating look is the one most people want and it is also the one with no floor support whatsoever. For both the two-feet and the floating installations you must use wall cleats fixed into the wooden studs behind. Decide which look you are going for before you start, because it changes whether the wall is carrying some of the load or all of it.

The screws that hold it to the wall are not in the box

Ulti-MATE states that additional hardware to attach the cabinet to the wall, such as wood stud screws, needs to be purchased separately, and their cleat kits note you may need to buy proper length wood stud screws at your own cost. Separately, French cleats are supplied with base and wall cabinets but not with garage lockers, where the hanging kit is a separate item. So the parts that actually attach your storage to the building are the ones most likely to be missing on the day. Sort them out with the order.

Cabinets are often wider than your stud spacing

A practical problem owners hit repeatedly: a cabinet wide enough to be useful does not conveniently land on two studs at sixteen inch centers. One documented solution is to fix strips of three quarter inch plywood horizontally into the studs across the whole run, then mount the cleats to the plywood with additional screws into studs where they line up. That gives you a continuous mounting surface, keeps a long run of cabinets on one level line, and is far better than compromising on where a cabinet sits because of where a stud happens to be.

Inventory the hardware first, because there are no spares

Owners report hinges and larger hardware packed in a separate box from the main hardware pack, and at least one found themselves a screw short with the cabinet half built. There are no spare fasteners included. Lay everything out and count it against the parts list before you start, work over the packing foam rather than a bare concrete floor, and keep fasteners contained. A single dropped cam lock on a garage floor is a genuinely annoying way to lose twenty minutes.

Two adults, and their own advice about hung base cabinets

Ulti-MATE asks for two or more adults when installing, noting the cabinets are very heavy, and their listings go further on one specific case: if you are hanging base cabinets, they recommend seeking a cabinet professional to install them, ensure attachment to wall studs, and reduce the weight load. That is a manufacturer telling you where the risk sits. A base cabinet was designed with the floor taking some of the load, so hanging one puts everything on the cleat and the studs.

Know what the warranty covers, and what it does not

The 10-year warranty is a limited parts warranty. Ulti-MATE states that they will not pay for service calls to install the product, to correct installation problems, or to instruct on how to install or use it. That is normal for the category and it is the same position NewAge take. The practical reading is that a defective panel is their problem and a cabinet installed badly is yours, which is a reasonable argument for getting the cleats and the leveling right first time.