Just make it large enough to carry enough fuel for landing.

Falcon heavy could just be the launcher for this idea.

Very roughly. For every ton of fuel to go up you will need the same to get down. Not including the first stages fuel.

Boeing is prime contractor for the American side of the ISS, which includes much of the day-to-day analyses and operations. The people you see on-console on NASA TV are NASA employees, but many of the people in the back offices those people talk to are Boeing employees. In fact, from what I have heard, Boeing provided substantial help to SpaceX between COTS 1 and COTS 2/3 to help get them qualified to berth with the ISS.

While SpaceX’s native capability has grown much since then, I doubt they have much, if any, advantage over Boeing here. Over Lockheed (prime contractor of Orion), sure, but not Boeing.

SpaceX tends not to say much, but pieces of the Dragon 2 (the human-rated Dragon) are known. They needed to start flying “flight proven” Dragons (done, with CRS-11), so they could convert production over to Dragon 2. There will need to be at least two uncrewed flights, one for in-flight abort test, and one orbital mission. Just a guess, but that mission would probably be a cargo run to ISS. After that, they might be able to get certified for a crewed mission. Timelines are open to guessing, but I understand that the expectation is for the first crewed mission to ISS could be in the first half of 2018. That could mean a first flight late this year.

Also, I understand that they are a few months ahead of Boeing. That probably is measured only in terms of capsule development. SpaceX is also proficient in flight management and logistics; while Boeing has a lot of experience in space, I don’t know how that compares to SpaceX. ULA would probably handle the launch, but once in orbit, I don’t know if they have much experience that is directly comparable to the rest of the mission profile. They did launch a couple of ISS supply missions for Orbital ATK. On the other hand, no one except SpaceX (in the US) has soft-landed a capsule since the last Apollo flights.

sayomara: In the story that I linked to in this post, the gap in launches in July into August is explained.

However, there will be a small gap ahead of the following launch, in part due to the Eastern Range undergoing a maintenance period. The following mission will involve the CRS-12 Dragon in the second week of August.

Other than the Falcon Heavy, we haven’t hear anything in a while about human dragon testing. Or the Falcon version 5 first stage, moving back to Pad 40 which should be happening soonish. Just a ton of SpaceX stuff it would be nice to know where they are at on, and maybe this gap is playing into many of these.