Is this Realistic, and How Much $$$ ?

[OandD4ever]

let me start by saying hi to everyone , i'm new here.
i know nothing more about boating then what i read online and saw in movies and instructional vids. so i'm working my way towards being a beginner.

i know that i like and hope to get the Sea ray 310 or the bayrunner with about the same specs.

below are the specs.

2009 Sea Ray 310 Sundancer® | Sea Ray Boats and Yachts

MY PLANS :
1, I"m planning on doing lots of fishing, inland and out a couple of miles. not that i have done much fishing in my life. but thats the plan.
2, i'm also hoping to be able to go on long cruises. go from NY to VA to FL to TX and back to NY. a trip like this would be done maybe once a year or so. if not less often
3, a trip to a nice island someplace far. would also be cool every long now and then.

the boat i'm planning on getting is a inboard 30' i know they don't get great MPG but is it realistic to be able to do these things i'm hoping to do? or is going to cost so much that i'm gonna have to be happy i'm fishing and forget the rest.

what would a long trip cost?

lets say a trip from NY to TX, how much can someone on a 30' powered cruiser expect to pay for gas?

any and all info would be greatly appreciated. really i mean any info. any at all. thanks again.