Why $ and not £ ? Only ask as if you are not in the UK, suggestions form the UK might not be as helpful.
I have not had any bad experiences on ebay, as long as you are able to recognise what you see (or don't see) in the listing, and ask the right questions if information is lacking or unclear.
If you don't get answers, leave it!
I have bought several things from this seller, and all have been superb and better than expected
https://www.ebay.co.uk/sch/i.html?_...13&_dmd=2&_oac=1&_trksid=p2047675.m3561.l2562
I have recently moved from Canon to Panasonic MFT.
You can get a G3 and 14-42 lens from anything from £50-100, they are light, easy to use, have many of the advantages of mirrorless and take very good pictures for very little money, right up to a G9 for anything from £550 to £1000 which can use the same lenses. (and of course new ones for a lot more)
A G5 and a 14-140 lens would come in under your budget, and makes a nice combination for family and out-and-about photos.
In Canon, if I was to look on your budget, I would look for a 650D or an 800D and a 18-135 lens.
Not suggesting that you go for any of those, just mentioning options I am familiar with, there are dozens of others.
As suggested, the best thing is to look hands on and see what suits you, and if you can't do that, spend as little as possible so that you can start using something and see which way you go.
No point in just going for the highest pixel count either.