Regarding "just reapply"... for another $3000? I'm certainly trying to avoid that. I'll start pulling together evidence of the house sale just in case.
Your IHS surcharge will be refunded if it's refused (though it can take up to 3 months to get it back), so the only 'extra' you would pay would be the £1,464 visa fee, plus priority processing if you chose to use it.
The thing is, what else would you do? Your options would essentially be to either reapply, or not move to the UK at all.
An appeal would take about a year and wouldn't be successful unless you did send all the correct documents and UKVI made a mistake in refusing the visa. So, you would probably end up wasting up to a year and a load of lawyer/appeal fees, only to have to reapply in the end anyway... and the visa fees would be even higher by then.
"Just reapplying" is normally the quickest, easiest and cheapest option... other than not moving at all, of course.