You want to hour build (for cheap) yet want to get a twin turbine rating with a ppl(h)?
That makes very little sense to me......
If you looking into going cpl(h) I dont think getting a twin with a ppl(h) will benefit you much.... its shear hours you want, so your gonna go SFH hire a AS355? should imagine there gonna charge you a grand an hour for that so you could probably have 6.6 hours on a R22 for 1 hour twin time..

Plus I cant see any owner/operator letting a ppl(h) pilot with less than 100 hundred hours take a £1.2 million helicopter for a ride around on there own can you? safety pilot for maybe 50-100hrs......? just a guess though.
Please let the pro's correct me if i'm wrong.........
Either way here CAPT online....
Caledonian Advanced Pilot Training - Multi-Engine