TBH keeping a lizard isnt cheap, so dont let the price of a crested gecko put you off.
You can pick them up for about £50 - £60 for a normal morph.
I would recommend a crestie for you as they are friendly, easy to care for, lovely looking, can be fed on dry foods and are nocturnal.
either that or a leopard gecko, they can be handled... how much depending on the lizard itself.
You 'can' get a crestie and setup for about £150...
Its down to budgeting.