Sigil: City of Doors

I am planning on starting up a group of pirates who sail around the Planes, and I was wondering what the cost for a spelljammer is. This may have been brought up before in another thread, but I'm exceptionally lazy when it comes to searching through hundreds of pages in a forum.

To elaborate further, the captain himself isn't actually a character yet, but I am planning on making him soon. The general idea of the pirate crew is that they do some mercenary work, as well as obvious pirating of other spelljammers. I also have a variety of questions regarding what would be possible with a player owned spelljammer, as well as how big they can get and what materials can be used to build them. Obviously, I won't commission the spelljammer if I don't have a crew to man it.

I'd also like a list of all of the Planes spelljammers are able to sail to, if they can sail on Planes that are not the Astral Sea or the Prime Material Plane. I'm also wondering if it is possible to fireproof the spelljammer if it cannot be made out of materials other than wood, as the captain is going to be an Efreet.

I believe these links might be of assistance to you.

Guide to pricing for player owned structures (This includes jammers and is priced by where they would be 'parked' normally)

A few examples of pre-existing spelljammer types/statistics and deckplans which could be used to help with the layout for the area that would need to be built.

To answer the other part of your question, where you ship can actually 'go' seems dependent on role-play or dm discretion during events, but mechanically speaking would not act as a portal to anywhere.

Yes, we do have one character who owns and lives in a spelljammer in sigil. Which is permanently parked and does not travel. I can promise that nobody will be boarding a physical 'jammer to jump from plane to place (with the exception of course of the ships that bear you to the Astral and Fire Plane areas, of course, or possibly in an EM or DM event), particularly one they own.

All you'll really be able to ever do is tell people "hey I own a spelljammer". If you want a character who can move quickly among the planes and has the IC facility to do so, you'll probably want to take some levels in the Gatecrasher class.