First time poster on here looking for some advice

My sister's garden is currently a wasteland - there's not much soil, some rubble and lots of weeds!!! She's leaving Ireland to move to Canada for a couple of years and is planning to rent her house (in Dublin) while she's away. I'm planning to fix up the garden a little so that it's low maintenance and is at least presentable.
My plan at the moment is:
1. Clear away the rubble and weeds
2. Lay some sort of "plastic" covering which will allow rain to percolate but stop weeds from springing up
3. Plant a few shrubs (miniature evergreens maybe?) through holes in the "plastic".
4. Spread pebbles / stones over the plastic covering
I know it's pretty basic but does this sound ok?
Is such "plastic" covering available? What do I ask for?
Any recommendations on plant types? Or what sort of stones to put down?
I also have a couple of other jobs to do like hanging a side gate and perhaps building a BBQ or something.
Thanks in advance
