Done the corporate stuff... And still doing a bit.. hopefully less and less (Knowcking wood).
However regarding type ratings. With very little experience it is close to useless to get a type... Your best chances to get a look is to build your hours up and keep updating your CV with companies you are interested in.
Regardless of your willingness to obtain a self sponsored type rating you should keep that info away from a prospective employer and only use that card when y really need it, that is if they offer you a job provided that you are typed.
If you read the above but still decide that it is within your best interest to pay for a type your self... Well. Have a look atthe companies you are interested in, what types do they operate. From a pure numbers point a Citation is probably most common entry level Jet. I would not even think about Gulfstreams or other heavy iron birds.
But then if you get a CE something rating and get hired by a company that operates Lears... Money wasted.