I would like to have my kitchen sink moved about 4 ft to opposite side

I would not leave out the plumber! Can't tell about the price before you get a professional's estimate. Plumbing is right up there with Electic that I don't do!!

If your plumbing skills are up to par, yes, you can do yourself. Check local building code to see if you need to pull a permit, (typically relocating plumbing and or electrical does require a permit.) If you hire out, I would not hire anyone that was not properly licensed. This is your house and your family. If something goes amiss . . . And your insurance company finds out you did not hire a licensed plumber, they can deny the claim.

https://www.fixr.com/costs/plumbing-for-kitchen-remodel

I'd first get a professional to come look at what you want to do. They may point out some obstacles you may not have thought about as yet. Ask them for a price to complete what you want......then, you'll know and have an idea of what all is involved and what you'll need to purchase and do to complete a diy. Access whether you have the skills, tools, knowledge to do it. Information is power. Anything can be done, but it may be more expensive than what you want to spend. The pro may also give you some ideas for other options you haven't yet considered.

It usually isn't good to go straight across with water lines. As already suggested, get a few plumbers in and get their suggestions and prices.

If you want to do this yourself, pex pipe is the easiest way to go and can be transitioned into existing piping. Check with your local codes before making any major changes. Good luck.

Thank you all for your advise I will have 2 or 3 plumbers come out and see what all is involved and choo one of them to do. Again thank you, your help is surely appreciated