Which one

[ngauger1]

That helps but what class should I buy?
I don't have a lot of money but don't want something that does last.
Would probably like a 12 wheel drive for more power since I will be pulling a circus train.
Any suggestions? (GP 40,GP50,ect)

[brokemoto]

B-mann sells an A-B set of F-7s.  They are good pullers.  Buy the SPECTRUM version.  If you see the older PLUS versions, I would avoid them.  The SPECTRUMS would be allright for your purposes.  The street prices of these things are not too bad.

[johnTom]

B-mann sells an A-B set of F-7s.  They are good pullers.  Buy the SPECTRUM version.  If you see the older PLUS versions, I would avoid them.  The SPECTRUMS would be allright for your purposes.  The street prices of these things are not too bad.

I agree with Brokemoto about the Spectrum locomotives.

[Albert in N]

Price and availability may be concerns.  Bachmann makes N scale beginner sets with GP40 and F9 diesels being common in sets.  I have both GP40 and F9 and can attest to their simplicity, durablility and performance.  Both require more current to start (10 volts on mine if they sat on shelf for extended period), but a Bachmann power supply has up to 16 volts DC, so no problem.  Once warmed up, less voltage is required.  My GP40s and F9 can each easily pull 8 Bachmann Silver Series cars around dog bone curved layout.  I also own a Bachmann Spectrum F7 A-B set in Southern Pacific colors.  It cost more than the GP40 and F9, but is more powerful and does not use traction tires like the GP40 and F9.  It doesn't need them and will pull many more cars and is better looking.  These locomotives all have swiveling truck mounted couplers and will go through Bachmann turnouts without problems.  The body mounted coupler Bachmann locomotives can derail cars on Bachmann turnouts.  Bachmann steam also derails loco and cars using Bachmann turnouts (at least they did on my earlier E-Z track layout).  The F9, GP40, U36B, and GP50 share the same power design.

[Albert in N]

Before you spend a lot of money, it pays to talk to your local hobby shops and go to area train shows.  If these are available in your area, you can likely see N scale layouts operating and talk to the people running the trains.  Also, if you know area N scalers, ask for their advice and look at their layouts.  While shopping for N locomotives, cars, track, and power supplies, compare prices and features.  Also, compare warranties and returns.  If you mail order, Train World has been a good source for me.  Once recently I had a defective locomotive (Spectrum SD45) and returned it to them on the same day that I received it.  Train World kindly gave me full credit that I used to upgrade to a better locomotive for the price difference.  One thing to watch for on ordering is coupler compatibility since many N scale items still have the ugly old Rapido (standard N) couplers that do not interface with Bachmann dummy couplers or operating couplers made by Bachmann or other sources.  Good luck and have fun!