As requested, a ship capable of the Kerbin, Mun, Kerbin, Mun, Kerbin mission. Disclaimer: I have not fixed the fuel bug on my version of KSP. My guess is that with the bug fixed, this ship would still succeed with just a few more tanks added to the upper stages. The stack: Further remarks: Launch phase must be throttled down as you pass 11k; must be below 2g or risk catastrophic failure. Begin roll at 11 k and aim for 80k holding orbit. Upon first landing on Kerbin, the parachutes slow your decent to 11m/s. Use throttle just before touchdown to slow further or damage to engines will occur.