[AccessD] importing from Excel

I'm wondering if any of you routinely see data type conflicts when importing
Excel data into Access? I spent an afternoon with a client a few weeks back
cleaning up Excel data for a clean import into Access -- we were totally
successful. We went from losing hundreds of records to capturing every
single one -- with just a few simple changes in their routine. 
 
The one potential problem I thought of that we didn't encounter was a
conflict in data types -- have any of you experienced this? My guess is
you'd simply convert using the Import Wizard, but I'd like to hear your
horror stories and solutions.  I know imports are often automated and that
complicates things. 
 
The client's experience was strictly a one-time effort. Once they got it in
Access and we normalized the data, they were done with that part for good.
They were trying to create a searchable/reportable archive of some very old
data and used Excel as the go-between -- but then couldn't get the Excel
data clean enough to import. The truth is, it was very easy to solve -- they
just didn't know the right tricks. So, now they want it all documented, but
I personally, haven't run into any data type conflicts while importing from
Excel, but I'd like to note any potential problems if they're out there. 
 
Susan H.