I think that you will need to have a good talk to the owner , if he/she has run that motel before they will know the issues. If not get them to stay and experience it.
I`m sure that you can come up with a solution , it may be that some money needs to be spent but if the guests are having trouble getting into there rooms it is not working properly and this will come up in reviews i would presume.
As the guests pay the bills , it needs to be uncomplicated and just work , once you sort that out ,i would think you will get many more nights in bed .
Maybe do some homework and cost it out for any changes you need before presenting them to the owner.
We are at the stage now that everyone pays on the way in and if no breakfasts which is nearly all the time nowadays we get to sleep in until 8am sometimes 9 am or untilthe kids decide to wake us up
good luck with it.