Experiences with capsaicin sprays to deter rodents.

Hi all, currently working with my dad to turn an old farmhouse into a little permaculture retirement residence. Everything is going great except for one glaring issue, rodents. The block is parked between mixed use grain/orchard farms and despite our best efforts the house is unoccupied 60% of the time. We’re southern hemisphere so winter is starting to hit and all the rodents are looking for a warmer place to find a home. Every time either of us comes down the first hour is spent cleaning up after the rodents that are finding a comfy place to rest in the house and it’s a pretty grim way to find your happy place.

All food is locked in sealed containers, has been for over a year, that isn’t the issue, any fruit bearing tree/vegetable is also 50-100m from the house, the cottage garden is clean and open. The only explanation is that the shelter itself is attractive. We’ve plans for laying a slab, sealing all gaps under the house, etc. but in the meantime we need some relief.

Does anyone have experience making a capsaicin extract to deter pests? Formula, application tips, we’re desperate. We’ve tried peppermint oil and all the gentle options (we’ve had native species around the house but they took off once the house was somewhat regularly inhabited), the rat bastards have shat in our tea cups and it needs to end.

Additionally my dad was an industrial chemist, if anyone has a potent concoction to guarantee success he’s the man to take it nuclear.