Finishing the Self paced in 90 days is a lofty goal. But I do think 4-5 months is very doable. The reason being, a self paced student has last priority when it comes to planes and checkrides. So you might get pushed back from time to time. let me rephrase that, It WILL happen. Just be patient and understanding of the fact that some people drive/fly from far away to get their ATP or MIFR add-on in 2 or 4 days. So if they have to bump you back to accomodate them, they will.
Good luck. If you want to do it in 90 days, why not just go to the RAL location. They have housing there. It doesnt cost extra. and you spend less time on the taxi way and more in the practice area, which is pretty much just outside RALs class D airspace. They have a mx base there, and the MX guys were great when I was there. Always willing to answer any questions we might have about the plane. In-depth answers that most students and instructors might not know.
RAL is still the greater LA area, which I assume you live in. So if you need to go home, you can just jump in your car and drive there.
If you really want to get it done in 90 days and going to be fully committed to getting it done (not working on the side), go to RAL. Otherwise you might be sitting in the LGB office getting ready to take your Intstrument checkride 90 days after your start date instead of being done had you taken my advice.