The paper considers possible variants of rocket engines for the project of a low-budget ultralight launch vehicle. Along with the existing engines, the option with a pressure feed is considered in detail, where the achievable indicators of mass perfection of the stages of such a rocket, the specific impulse of the engines and the share of payload are analyzed. A technical and economic analysis was carried out, which showed the dependence of the cost of the launch vehicle and the specific cost of launching cargo into orbit on the engines used in the first and second stages. It is shown that the creation of a rocket powered by pressure feed engines leads to simplification and cheapening of engines in expense of the complication and increase in the cost of the feed system and tanks, which ultimately reduces the cost of the rocket with a constant launch mass, but increases the cost of launching the payload. Among the existing engines, the use of relatively low-pressure open-circuit engines is justified, and configurations of light and ultralight missiles based on them are proposed, which have a minimum launch cost and a minimum specific launch cost.