I am about to process the same.

visit Visa is only temporary. i think 1 month then can extend to 6 if pay 100 or 200 riyal a month. you can then transfer visit Visa to residence Visa (get rp) for 500 riyal.

residence Visa should take 10-20 days to process but will need a pile of documents too and some of it will need to be translated to Arabic and then stamped by your embassy then by mofa so there is a couple of days of running around getting everything ready. my company will help me process it, I think most companies will assist