Start cheap and work up to a high quality tent if your family enjoys camping. I have 2 Ozark trail 10 x 12 tents I have used many times over the last 10 yeArs. Neither have been waterproof and I have never gotten wet!
But like others have said put a sheet of plastic or tarp under your tent and put a tarp over your tent plus lay your tent out in the driveway or hang it up in the carport to dry before storing. Make sure to get a big enough tarp over top to run water away from the footprint.
And the most important of all....use a tarp under your tent and make sure it is 100% dry when you pack it up. You can make any tent last years if its well kept.
A cheap tent and a huge tarp, plenty of rope and ratchet straps. I still use an old canvas Hillary tent from sears. It's over 30yrs old. I wouldn't get one too big that it won't fit on tent pad (if you go to places with a tent pad). You don't want the water running under your tarp. Dig a small trench if you have to. Nothing will make you say more bad language or turn you off from camping all together than a big downpour. We had our share last year.
Disclaimer, an Eno hammock, bug net and rain fly hanging from Eno straps is more money than a tent.
But I am not looking back...
I have an Eno but my wife and son can't sleep in it. Thanks for all of the suggestions! Looking forward to camping soon.