It is scary, but only if you do not get the right advice.
Mr Knowall down the local bar is one to avoid.
I always quote an example.
My friend was told by the typical expat expert down his bar, 7 years ago, 'oh you can't get residency cos you rent'
So he did not apply. Now he has insufficient funds and income to qualify. With Brexit, he is worried.
If he had taken proper qualified advice he would have got residency in 2011.
Proper legal advice in Spain is mandatory!
Its usually a bargain villa or finca for a reason, especially if it is set in its own grounds.
Don't be put off, get a Spanish Abogados approval. Its not hard to find an English speaking one.
You can enjoy your life in Spain.
Good luck for your future.