Critters under mobile home

Moved into a 20 year old mobile home in the Arizona desert and have been happy until now. As the temperature is dropping at night I am starting to hear critter(s) moving around under the house during the night. When we remodeled we put aluminum window screen in all the floor heater vents and all places where there were access points into the house but there is no way to seal under the house (stem wall foundation but no way to completely seal). Nothing has gotten in, or at least there is no evidence of that inside.
We have the electronic stuff and that may/may not have worked until the weather started to get cold.
Have read about everything from mothballs, lights, traps, poison ...etc.
Has anyone here dealt with this from a mobile home in a rural desert area perspective?
I am new to the forum but in RV, Car and other forums I have found great advice. I am sure I will here as well. Thanks in advance for good ideas.
ZT

 

Do you have an idea of what the critters are? I'm assuming rodents, but mice, squirrels, rats (or bigger) or maybe a little of all? I know you guys have scorpions out there too, are they a possibility?

I don't have any faith in the electronic repellers or moth balls or equivalent.

If rats, then we'd want to use rat-sized snap traps. If you used mouse traps and the rats set them off then that would make the rats trap shy forever so don't set mouse traps if rats are a possibility. The rat-sized snap traps that have the expanded triggers on will also catch mice. This is an example of a trap with an expanded trigger. I don't like glue traps as they don't always hold the rodent and even when they do, it will squawk and carry on loudly which usually happens late at night when you least want to go under there.

https://www.domyown.com/victor-rat-t...aps-p-223.html

 

The critters seem to be mostly mice. My problem is I cannot get under the house myself because of disabilities. Rats are not known much in this area, but mice, squirrels (less) and skunks and stuff are. Tarantulas are also friends out here, but they go after things I dont want like snakes and scorpions.

I have heard something at night that seemed larger but that may just be a mouse in a space that created noise.

I am pretty sure the mice have gotten into the duct system but of course I cannot get under to repair it.

 

Is there any kind of access door to the crawl space underneath? If so, could you or someone put rodenticide into an exterior type bait station and push it under the crawl? It would have to be checked and maintained probably once a week at first, with ensuing frequency determined by activity in the bait. I always preferred the bait blocks.

 

There is a crawl entry, kind of like a storm cellar opening to get under the house into the crawlspace but as mentioned before I cannot get under there due to disabilities. The problem with the entry is that it is at the opposite end of the house from where I get the critter activity (56 feet away) so the crawl is a long way.
I have the area completely wired (metal window screen and 1/4" garden wire. But of course the critters can always find a way in if they are creative.
I have placed baits around the perimeter of the house and so far have gotten a few mice. Big mice as you would expect in a field/desert environment. No little ones like in the city. Peanut butter is working well!
I dont know if I can eliminate them, but working on management of the herd!