Lots if them on the market. We have a WM 500, I believe, and it runs the small appliances, laptop, tv, etc. Just figure how much power you need and proceed.

Found one at Walmart. plugs into 12v outlet and has one plug in for 110. I use it for phone chargers, computers etc. Don't remember the price but couldn't have been much more than $20. Don't know the wattage.

Try Harbor Freight, they have several sizes and they often have them on sale.

Saw that quote on a web site when I searched for dremel tool running on power inverter.
I didn't do a lot of reading on the issue yet but I believe that a lot of devices, especially those with variable speed controls, do not like the modified sinewave output of the cheaper inverters. You may want to check into that!

I had a 500 watt inverter I picked up at West Marine. Note I said 'had' as it died an unnatural death last season. It worked OK for charging things, TV/DVD player; but it would NOT run the small, handheld vacuum cleaner I keep on board. The motor should have been less than half the inverter rating, but it would beep and scream and trip it's breaker any time I tried to use that vacuum. So yes, be aware that some things, even simple things like a vacuum cleaner motor, may not like the modified sine wave inverters. I've yet to try my Dremel tool, so can't comment on that specifically.

You would hope that manufacturers of small inverters would ensure that the DC current draw at max power would be safely handled by the wiring used for the 12V plug-in connector, but the fact is that the wiring is part of the boat, so no guarantees there.

If you need to have a larger inverter, make sure the appropriate size DC cables are connected to the battery bank (with fusing). Keep in mind that if your 120V appliance is rated at 10A, you will likely be drawing over 100A on the DC side (accounting for conversion inefficiencies). That is not a trivial amount and the cables need to be able to handle it safely.