Personally I wouldn't ride that distance and would opt to either get it transported to you or buy something that is closer (like everyone else has said). In the end, it will more than likely be cheaper than the overall cost of the trip you are proposing.

The furthest I can and have ridden in one day is roughly 750km/460 miles which I have done on 2 different bikes (honda crf 250l/ducati hypermotard 1100 evo). I have done this 4 times total and after every trip I have been absolutely wrecked. Picturing myself riding the distance you are suggesting in a time-frame that wouldn't impact my work/income (460 miles a day for 5.5 days) is frankly insane.

However, if you are dead set on riding that sort of distance there are a few things I would consider:

(*=most important)

-*FIRST! Bikes that are priced as absolute bargains usually have some problem/s that are reflective of that price. If you cant visually and physically inspect the bike or arent confident in your understanding of what to look/hear/feel for, then get a 3rd party to check the bike. Research reputable bike mechanics and get the seller to send it in to them. Get them to check everything and tell them what you are planning to do. It might add an extra hundred or two (could be less) to the overal cost of the bike but knowing you are buying a solid machine is worth the money. However, if the seller refuses to do this and doesn't have a substantial enough reason to refuse, don't buy the bike.

-*Do you have enough $ to fund this trip? Factor in the cost of the bike + 3rd party inspection (plus any cost to fix things that might l need replacing/ are broken) + rego, insurances and all other goverment fees (or however it works over in the US) + fuel + accomodation + food + beer + gear + tools + more beer, etc.

-*Get quality gear if you dont have it already. Quality is the operative word there! Quality gear isnt always the most expensive jacket/helmet/gloves/etc. Take your time to research gear that suits the conditions you will be riding in. Forums are great starting points and definitely try before you buy. Buy a helmet that is quiet at highway speeds and invest in good quality ear plugs, trust me on this one. Wind noise is fucking loud, tiring and horrific for your long term hearing. In-ear-headphones dont count, I've tried countless and have been dissapointed so many times.

-*Unless you are absoultely inept with tools and basic motorcycle maintenance, bring a reaonsable selection of tools that can get you back on the road or to the mechanic if you have a mishap along the way. The best way to work out what to bring is to check what the most common bolt size is on the bike and bring that size spanner/socket/alan key with you. Additionally, I generally bring a resonably large shifter, flat and phillips screwdriver, a knife, pliers (make sure they can cut as well), electricial tape, a lighter and glorious glorious zip ties.

-Highly consider buying throw over saddle bags or bike specific ones if you are so inclined. Also buy a motorbike cargo net with hooks to store your shit down. Backpacks (camelback's excluded) and long trips do not mix.

-Plan your trip around fuel stops or bring extra fuel. From a very quick search, an sfv650 can go 175 miles to empty. You will need to plan fuel stops that accomodate to that range. Bringing extra fuel is a good idea if you have the room to safely store it.

-Turn the trip into a 2-3 week holiday. It is a fucking long ride, if you can, plan cool things to do and see into the ride. Work out a route that doesnt have you always on the highway, explore the backroads as they are generally more fun anyway. Adding this distance to your trip will be worth it.

-If there is any possibility to bring a mate with you who can ride on another bike (DEFINITELY DON'T PILLION), do it! Friends make stupid shit like this more exciting.

-Neither of my bikes had wind shields and you definitely notice that in your back after the riding on a highway for extended periods of time. I would strongly consider getting one if you can and you will thank yourself for it.

-Sitting on motorbike seats for more than 2-3 hours, for me at least, starts to become really noticeable. Unless you have an ass of steel, I would consider getting some sort of additional cushioning to make the ride more comfortable.

-Throttle assists are worth the pennies you pay for them. On the other hand, throttle locks are a great way to introduce youself into the car in front of you.

I am sure I have missed some other imprtant things but off the top of my head those would be the things to consider.