Are there holes pre-drilled for bolting to the floor?

No pre-drilled holes in the safe. My safe came with 2 - 4" lug screws, 2 washers, and 2 masonry anchors. To anchor safe to the floor, one has to tip the safe on its side and drill holes through the bottom at two indentations on opposite sides of the safe, using a 7/16" , masonry bit. Then sit the safe upright and place it where you want to secure it to the floor, mark the floor (through the drilled holes), move the safe aside, drill into the floor using 9/32" bit for wood floor or a 3/4" masonry bit for masonry floor (then install the masonry anchor in each hole); in either case, drill holes 2 1/2" deep into the floor. Move the safe back over the holes; for wood floors, insert the screw through the washer, through the holes in the safe, and into the holes in the wood floor - tighten with a wrench. Do the same for masonry floors and tighten with a wrench. Hope this helps.

(1) Can you change the combination? (2) Do you need both the key and the combination at once to open, or is the key an "override" ? Thanks.

I'm not sure why people are saying you can't change the combination, but the user manual provides instructions on how to add your own "user code" and even temporary "user pins". The factory code can't be deleted but if you just set up your own user code you can change that anytime you want. In case this is Amazon being weird and linking these answers to a different product, my answer is for the electronic combination lock product (SFW123FUL); per the same instructions, the physical combination lock version does not allow for changing the combination.http://www.sentrysafe.com/pdfs/OwnersManuals/513023.pdf

can this be bolted to the wall thru the back or to the floor?

There are two designated spots for you to drill through that is located on the very bottom shelf inside the safe. You drill through those two spots and use the included mounting hardware and this safe isn't going anywhere. There are no designated spots to drill through the back/side so it is not wall mountable. I would understand why because most homes have drywall so the drywall could be demoed around the safe and then the safe can be taken. Ripping up the floor (carpet, wood, sub flooring, concrete, etc.) will take a lot more effort when this safe is properly mounted to the floor from within the safe.

is the handle plastic? i had a previous sentry safe and the handle was plastic and felt like it would break

Yes, the outside of the handle is plastic, but I believe the actual handle mechanism is metal. When you're opening it, the motion feels solid so at least the innards is metal. If someone tries to turn the handle without knowing the combination, there's a feature that is meant to allow the handle to still turn without engaging the bolts. This is a security feature.

Brand	SentrySafe
Product Dimensions	18.8"D x 16.4"W x 13.7"H
Lock Type	Combination, Key
Color	Black
Capacity	0.81 Cubic Feet
Material	Durable Resin Wrapped Concrete
Special Feature	Fireproof, Waterproof
Mounting Type	Freestanding, Tabletop
Included Components	SentrySafe Combination Water and Fireproof Safe with Override Key
Item Weight	55 Pounds
Alarm	Audible
Water Resistance Level	Waterproof
UPC	049074032340
Manufacturer	SentrySafe
Part Number	FPW082K
Item Weight	55 pounds
Item model number	FPW082K
Style	1-Hr. Fireproof, Combination
Item Package Quantity	1
Number Of Pieces	1
Special Features	Fireproof, Waterproof
Batteries Required?	No
Warranty Description	Limited 1 Year Warranty

Large 0.81 Cubic Feet Fireproof Safe with Dial Combination Lock for Home or Office Protects Money, Documents, or Other Valuables, FPW082K

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