Yes, their standard of living would go down in terms of what they could buy, however that might be offset by the benefits of Hawaii vs Chicago and trying something new.
That said, I’ve never actually been to Hawaii. It looks great in the movies but other than the weather I don’t know what it’s like to actually live there in terms of day to day stuff to do and cost of living.
Your “standard of living” need not go down at all if your income / assets well exceed your needs.
The OP already said all he’d be doing is spending more of his (well off) kids’ inheritance.
Comparatively few people have that luxury, but if you are one, my advice is: Ride that bitch to exhaustion! Yours or its.
That’s my motto and I’m living it as hard as I can.
I have relocated my family 8 times , 6 were international and the last two were from from Park City to Houston, then back to Park City.
All but the last ones were company dictated moves. The last one I quit and changed industry to get back to the mountains so it was a quality of life decision, but fortunately the hiring company paid to relocate me.
Even with relocation paid for , there will always be a bunch of expenses that seem to sneek in , new appliances , vehicle registrations , etc so budget for that.
Personally I’d sell the house and stick the money in a stable investment and rent in Hawaii particularly if you are not sure if you will stay in Hawaii. Unless you can buy outright the over heads of mortgage fees , inspections , and all that crap involved in buying a house adds up and could be a few years before breaking even particularly with today’s interest rates .
Then when you move back you can get something somewhere you plan to retire to .
Renting out a house is a pain, maintenance, getting the right tenants, you are limited in when you can move back etc .
Depending on the relocation deal, companies sometimes will pay the house selling fees and the realtor fees , which can be 6% so that’s a good chunk o change . Depending how it is done there are some tax implications and they may use a relocation company that basically buys you house then sells it back to back to the new owners . It is a bit of a cluster but 6% of a house is a penny or two.
Some stuff can’t be moved ( liquids oils etc) but moving is a good opportunity for a purge of stuff that builds up. On one move we had a box that was still sealed from the prior move , so that got tossed , and the moving people who pack and shifted our stuff have done well over the years as we have offloaded lots of stuff beds furniture etc that we didn’t want to move.
Family. The one thing we missed was family , having parents around for random babysitting , watching the kids for a few days etc was missed. I know you are on the other side of that equation, but don’t under estimate the family side of things .
Personally I’d sell the house, purge stuff, put the keeper stuff in long term storage . Head to Hawaii with a couple of suitcases and rent with minimal things for a few years and enjoy the place. Then decide if you want to stay and buy or retire and go back and buy something else in a place near your family .
Thanks all. For a brief while I was thinking I might as well send in the application. Could always say, “No” if offered the job. And that way at least I won’t later be thinking, “Maybe I should have…”
But most recently I’m thinking it just would be a tremendous hassle and expense - more than we want to put up with right now. When we really started thinking about selling/renting our house, getting rid of/storing/moving our stuff, paying for kids/grandkids to visit - and then reversing it in 2-5 years, that just seemed like A LOT of hassle and expense. Adding in the not seeing the kid/grandkids. (They just started taking skating lessons, and the older one seems quite into it. My wife is a BIG skater and took them skating yesterday. The kinda thing you can’t do via zoom.)
Given our favorable and comfortable financial situation, what strikes us as a preferable option might be to consider relocating from Chicago to somewhere warm for the entirety of January and/or February. That would very much be an option for us when we retire, and would not involve the relocating hassle. Heck, I could even take 2-4 weeks off now while working if we wanted to. And the expense of renting for 1-2 months/year might not be all that more than the expenses moving to Hawaii might involve. (Just spending our kids’ inheritance in any event! ;)) Plus, we could go to a different warm place every winter. If we stayed in Hawaii, we wouldn’t have to stay in Honolulu (not fans of big cities.)
Likely, to some extent, we are both being lazy and chicken. Thanks for being a sounding board. I’ll let you know if we change our minds yet again!
Seems to me that you’re very happy and comfortable where you’re at now. And have the means to go vacation in Hawaii (or other locations) for extended periods if you choose to, as you’ve noted. If that translate into being lazy and chicken, then I am lazy and chicken too. But I like my comfort and my current home too. All my stuff is there.
But it is fun to think about such adventures.
Aww, that’s sweet your relationship with your grandkids weighed heavily on the decision.
When I lived in St. Louis and worked traveling the USA I’d always take the month of Feb as my annual vacation. Then go to the Bahamas or wherever while my co-workers were freezing at home and suffering the winter weather disruptions every day at work. Sux to be them.
At least in my line of work, very few people want Feb vacations, so even if I was lacking in seniority I still got what I wanted.
Can recommend.
Well, it should come as no surprise to anyone familiar with my body of work that I’m really just a big old sweetheart! 
Yeah - one guy in my office used to do that. I never thought it worth the hassle, and have been more along the lines of “a few days/no more than 2 weeks here or there.” But things change.
Thinking about this has been a useful exercise.
I’ve relocated a few times in my life. I can’t say I’ve ever really regretted it, though I could have made better choices once or twice.
But, you only live once. There’s the quote: nobody on their deathbed ever said “I wish I’d spent more time in the (same) office”.
By the way, I wouldn’t sell the house if you’re expecting to return to the same location.
That 6% realtor fee is heinous! True there are issues with renting, but if you can find a good agent you can at least break even on the expenses, and the value will probably increase over a few years.
Go on, live a little! 
Upon further review, it looks to me like you have a golden opportunity for a test drive here. If you have vacation time coming, why don’t you apply for the transfer, take some vacation time, fly to Hawaii, and spend time looking at housing, grocery prices, etc. When you get back home you can look at the numbers, the downsides of being 4,000+ miles from your grandchildren, and the upside/downside of uprooting your life for two years. If you decide to go for it, you’ll be better prepared. If not, you can withdraw your request to transfer.