Late fees for both home and lot leases?

For those of you who have separate home and lot lease agreements, how do you handle late fees? Do you just have a single late fee for both agreements (if so, on which agreement do you specify the late fee?) or do you have a late fee for each agreement? Have any of you had trouble with either method?

We have the late fee specified in the Lot Rental Agreement since the mobile home may be unoccupied for some time and the owner is responsible for the lot rent regardless. Use to have that the tenant was responsible, but then had one tenant who did not pay for 3 months and had to engage legal to get the owner to pay it via a lien.

So we basically implemented a Lot Rental Agreement Late Fee.