Let me clarify my post a bit. At 18yo unless every male in your family has a propensity to cardiovascular disease 2 dozen eggs a day isn't going to negatively effect you on a bulking phase of a regimine. I'm not stating to make 2 dozen eggs a day a staple ongoing forever. But during bulking. 8 12 weeks.
And also I'm suggesting eggs since they are cheap and at 18 you are probably on limited funds. Also the post wasn't a diet regimine in whole. The shakes are in addition to 3 real meals a day. The shakes add a cheap but moreover a convenient way to get the calories down.
I've eaten 3 dozen eggs a day myself for a whole winter and never had elevated cholesterol. But I also don't have heriditary propensity to cardiovascular disease. Diabetes is another story.
My point was eggs is a great source and the cheapest and a convenient method to get both calories and protein down your gullet. Eating more is a given. My suggestions is a cheap way to do so and safe as long as is for a limited time and 8-12 weeks is limited.
It's not very difficult to prepare 3 shakes pack them in a cooler and bam you got at least 300o convenient calories at your disposal.