IMO is all a scam on that end for a single meter most places are going to be high.
I recall the 88 was discontinued a while back they were just for automotive, had the RPM lead and the sort... that was based on a 87 which is a very robust meter, most likely too robust last too long, they still make a version of the 87, no RPM lead on those. So parts for an 88 will be high, but displays cross over to the older version of the 87s, should be cheaper, if you are using the RPM and the auto stuff its good meter to repair, the newer 87 is around $375 no RPM, they don't fit my needs. We have one 87-V.
I had my 88 repaired a few years ago, its still kicking use it as a shop meter now. Gets calibrated every year. Never had an issue calibration wise, clear display was cracked and died at one point.
If the normal route of fixing it yourself, with. parts kit does not work....
ETI is good as well, little bit high at times on the repair, maybe your shop will cover it, I know I have fixed and calibrated folks personal stuff over the years, it gets buried in the mix. I have spent about $100k with ETI on cal and they build equipment have one really nice test set from them, never had an issue to speak of.
https://electricaltestinstruments.com/
ETI has been doing my on site cal for 10 or 12 years, I spend about $3,500 in annual calibration, takes about 2-3 days to do all the stuff I have, not just handhelds, plus my time and usually 1 other person, plus shipping, plus the headache of chasing 15 people down to track all their crap, then try to ship it out and make sure they have what they need for that day. Usually end of August.
Thats why I do all our torque wrenches anymore, was about $4k for the stuff saved me about $1.5k per year, they were getting really pricey to do, and I had to go to 6mo per check, so that would have doubled that 1.5,,,, anything calibration or repair for electrical stuff is a scam....
Found one quote from Byram back in 2012 wanted $202 to calibrate the ET-88, IMO that was a bit high even for todays pricing, but the 73 meter listed was only $22.50 to eval for repair, turned out the 73 had a lifetime warranty was a old friends meter and fluke repaired or replaced the whole internals. Who knows what the min repair eval is. ETI, will be higher on that than Byram is my guess.
The 88 repair when I bought mine was not lifetime in my case can't find the repair paper for that one.