The cheapest way out is harbor freight tools. They have a $25 trim router and probably a straight cutting bit with bearing for $10 or so. What are you routing? if it's mdf or particle board, no problem. if plywood, its a little sketchy.
If you go this route check back for advice, there's a lot of potential issues. Trim routers have square bases and no template guides so you have to have a guide bearing bit. No plunge capability so you have to be able to drill a starter hole. Remember you're breaking a rule about cheap import tools: you are buying a potentially dangerous, precise and complex tool so prepare for compromise. Should be able to accomplish 4 holes anyway.
Routers also multiply like rabbits. I currently have 6 of varying sizes.