FwC

I'm here in phoenix, AZ. Got a major leak with the coolant on my '93 ES300. Took it to Toyomotors to have a diagnostic done (very nice folks there). But they listed a lot of things that needed to be replaced on the engine that has 120,000 miles. Some notes they left on my advisement if i were to get the work done "Timing belt kit/remove all parts and covers necessary to replace timing belt. While front of engine was exposed, customer opted to replace cam and crank seals and water pump as preventative maintenance, due to labor savings. Reinstall and torque all items to specs." approx = $850-$900

But then I went to Larry Miller Toyota, explained what needed to be changed what they listed were "valve cover gaskets, plenum gasket, crank seal, cam seal, timing belt, water pump rings, misc" $950 OTD.

I would like to know how hard this job is, am I getting what I'm paying for, is it a guarantee to solve my leak? Any other advice?