It wasn't long ago that nearly every model on a layout was either built entirely from scratch or from a kit. Ready-to-run models were associated with inexpensive train sets and toys. Many good models were available as kits that could be purchased inexpensively and assembled quickly. More advanced "craftsman" type kits were and are also available.
While kits of all difficulty levels can still be found, the era of the "shake-the-box" kit has largely come to an end. This is in many ways unfortunate as those simple kits were a great way to gain early modeling experience and to build larger rosters of rolling stock without breaking the bank. There are a few manufacturers who still market their equipment as inexpensive kits.
The HO scale kit for this tutorial is made by Accurail, model No. 2051. Accurail calls this the “ACFX Blue” car – it is an ACF Centerflow covered hopper leased to the Tenneco Corporation. It is one of over 100 paint schemes offered for this model for a list price of $14.95. Many of their other kits are even less expensive.
Unpack the model and familiarize yourself with the kit components. Once you know what to do, basic assembly of this model takes only a few minutes.