Regrouting and re-siliconing shower enclosure - how long to do properly?

[Skipsteer]

How long would it take a Tiler to properly regrout (remove old grout and reapply new grout), as well as remove old silicone and re-silicone within a moderately sized shower enclosure, approx 118cm L x 90cm W x 220 cm H?

Pictures also attached.

If only a few of the tiles show hairline cracks (see pictures) would you need to get everything regrouted, or just around those tiles?

Main issue and reason for the work are 2 small corner leaks (wet to touch but not drippping wet) on both sides just outside the enclosure where there is some silicone around the bottom outside corner cut tiles.

I've been quoted £250 to get this work done by a tiler (via MyBuilder), but he's only planning to set aside an afternoon to do the work, with another job in the morning. I had assumed he quoted me a day rate or close enough

Im worried he's not going to have enough time and will inevitably rush the work and I might end up still with the same problem if this is the case.

Would you expect this work to take more than an afternoon and ideally should I insist on the silicone work being done 24+ hours after any grouting work so that it properly sets and seals?

 

[opps]

Removing the grout and silicone is the best part of a day.

You can't grout and silicone in one day.

 

[Skipsteer]

That's what I was worried about!
And how can you silicone around fresh grout?
At some point they need to meet and surely the silicone won't stick to the grout.

Although in saying that, a few of the other tilers I spoke to also seemed to suggest grouting and silicone the same day.
Not sure if they were thinking more along the lines of cleaning up the grout and applying an expoxy-sealant without needing ro do a full on regrout.

A lot of tilers / tradespeople must be doing this though, so I wonder how bad it could be in practice?